900 (number)

900 (nine hundred) is the natural number following 899 and preceding 901. It is the square of 30 and the sum of Euler's totient function for the first 54 integers. In base 10 it is a Harshad number.

← 899 900 901 →
List of numbers — Integers ← 0 100 200 300 400 500 600 700 800 900 →
Cardinal	nine hundred
Ordinal	900th (nine hundredth)
Factorization	2^2 × 3^2 × 5^2
Divisors	1, 2, 3, 4, 5, 6, 9, 10, 12, 15, 18, 20, 25, 30, 36, 45, 50, 60, 75, 90, 100, 150, 180, 225, 300, 450, 900
Greek numeral	Ϡ´
Roman numeral	CM
Unicode symbol(s)	CM, cm
Binary	11100001002
Ternary	10201003
Octal	16048
Duodecimal	63012
Hexadecimal	38416

In other fields

900 is also:

• A telephone area code for "premium" phone calls in the North American Numbering Plan
• In Greek number symbols, the sign Sampi ("ϡ", literally "like a Pi")
• A skateboarding trick in which the skateboarder spins two and a half times (360 degrees times 2.5 is 900)
• A 900 series refers to three consecutive perfect games in bowling
• Yoda's age in Star Wars

Integers from 901 to 999

900s

• 901 = 17 × 53, happy number
• 902 = 2 × 11 × 41, sphenic number, nontotient, Harshad number
• 903 = 3 × 7 × 43, sphenic number, triangular number,[1] Schröder–Hipparchus number, Mertens function (903) returns 0
• 904 = 2³ × 113 or 113 × 8, Mertens function(904) returns 0
• 905 = 5 × 181, sum of seven consecutive primes (109 + 113 + 127 + 131 + 137 + 139 + 149)
  • "The 905" is a common nickname for the suburban portions of the Greater Toronto Area in Canada, a region whose telephones used area code 905 before overlay plans added two more area codes.
• 906 = 2 × 3 × 151, sphenic number, Mertens function(906) returns 0
• 907 = prime number
• 908 = 2² × 227, nontotient
• 909 = 3² × 101

910s

• 910 = 2 × 5 × 7 × 13, Mertens function(910) returns 0, Harshad number, happy number
• 911 = prime number, also the emergency telephone number in North America
• 912 = 2⁴ × 3 × 19, sum of four consecutive primes (223 + 227 + 229 + 233), sum of ten consecutive primes (71 + 73 + 79 + 83 + 89 + 97 + 101 + 103 + 107 + 109), Harshad number.
• 913 = 11 × 83, Smith number,[2] Mertens function(913) returns 0.
• 914 = 2 × 457, nontotient
• 915 = 3 × 5 × 61, sphenic number, Smith number,[2] Mertens function(915) returns 0, Harshad number
• 916 = 2² × 229, Mertens function(916) returns 0, nontotient, member of the Mian–Chowla sequence[3]
• 917 = 7 × 131, sum of five consecutive primes (173 + 179 + 181 + 191 + 193)
• 918 = 2 × 3³ × 17, Harshad number
• 919 = prime number, cuban prime,[4] Chen prime, palindromic prime, centered hexagonal number,[5] happy number, Mertens function(919) returns 0

920s

• 920 = 2³ × 5 × 23, Mertens function(920) returns 0
• 921 = 3 × 307
• 922 = 2 × 461, nontotient, Smith number[2]
• 923 = 13 × 71
• 924 = 2² × 3 × 7 × 11, sum of a twin prime (461 + 463), central binomial coefficient ${\displaystyle {\tbinom {12}{6}}}$[6]
• 925 = 5² × 37, pentagonal number,[7] centered square number[8]
  • The millesimal fineness number for Sterling silver
• 926 = 2 × 463, sum of six consecutive primes (139 + 149 + 151 + 157 + 163 + 167), nontotient
• 927 = 3² × 103, tribonacci number[9]
• 928 = 2⁵ × 29, sum of four consecutive primes (227 + 229 + 233 + 239), sum of eight consecutive primes (101 + 103 + 107 + 109 + 113 + 127 + 131 + 137), happy number
• 929 = prime number, Proth prime,[10] palindromic prime, sum of nine consecutive primes (83 + 89 + 97 + 101 + 103 + 107 + 109 + 113 + 127), Eisenstein prime with no imaginary part
  • An area code in New York.

930s

• 930 = 2 × 3 × 5 × 31, pronic number[11]
• 931 = 7² × 19; sum of three consecutive primes (307 + 311 + 313); double repdigit, 111₃₀ and 777₁₁
• 932 = 2² × 233
• 933 = 3 × 311
• 934 = 2 × 467, nontotient
• 935 = 5 × 11 × 17, sphenic number, Lucas–Carmichael number,[12] Harshad number
• 936 = 2³ × 3² × 13, pentagonal pyramidal number,[13] Harshad number
• 937 = prime number, Chen prime, star number,[14] happy number
• 938 = 2 × 7 × 67, sphenic number, nontotient
• 939 = 3 × 313

940s

• 940 = 2² × 5 × 47, totient sum for first 55 integers
• 941 = prime number, sum of three consecutive primes (311 + 313 + 317), sum of five consecutive primes (179 + 181 + 191 + 193 + 197), Chen prime, Eisenstein prime with no imaginary part
• 942 = 2 × 3 × 157, sphenic number, sum of four consecutive primes (229 + 233 + 239 + 241), nontotient
• 943 = 23 × 41
• 944 = 2⁴ × 59, nontotient
• 945 = 3³ × 5 × 7, double factorial of 9,[15] smallest odd abundant number (divisors less than itself add up to 975);[16] smallest odd primitive abundant number;[17] smallest odd primitive semiperfect number;[18] Leyland number[19]
• 946 = 2 × 11 × 43, sphenic number, triangular number,[1] hexagonal number,[20] happy number
• 947 = prime number, sum of seven consecutive primes (113 + 127 + 131 + 137 + 139 + 149 + 151), balanced prime,[21] Chen prime, Eisenstein prime with no imaginary part
• 948 = 2² × 3 × 79, nontotient, forms a Ruth–Aaron pair with 949 under second definition
• 949 = 13 × 73, forms a Ruth–Aaron pair with 948 under second definition

950s

• 950 = 2 × 5² × 19, nontotient
  • one of two ISBN Group Identifiers for books published in Argentina
• 951 = 3 × 317, centered pentagonal number[22]
  • one of two ISBN Group Identifiers for books published in Finland
• 952 = 2³ × 7 × 17
  • 952 is also 9-5-2, a card game similar to bridge.
  • one of two ISBN Group Identifiers for books published in Finland
• 953 = prime number, Sophie Germain prime,[23] Chen prime, Eisenstein prime with no imaginary part, centered heptagonal number[24]
  • ISBN Group Identifier for books published in Croatia
• 954 = 2 × 3² × 53, sum of ten consecutive primes (73 + 79 + 83 + 89 + 97 + 101 + 103 + 107 + 109 + 113), nontotient, Harshad number
  • ISBN Group Identifier for books published in Bulgaria. Also one of the Area Codes in the South Florida Area
• 955 = 5 × 191
  • ISBN Group Identifier for books published in Sri Lanka
• 956 = 2² × 239
  • ISBN Group Identifier for books published in Chile
• 957 = 3 × 11 × 29, sphenic number
  • one of two ISBN Group Identifiers for books published in Taiwan and China
• 958 = 2 × 479, nontotient, Smith number[2]
  • ISBN Group Identifier for books published in Colombia
  • The millesimal fineness number for Britannia silver
• 959 = 7 × 137, Carol number[25]
  • ISBN Group Identifier for books published in Cuba

960s

• 960 = 2⁶ × 3 × 5, sum of six consecutive primes (149 + 151 + 157 + 163 + 167 + 173), Harshad number
  • country calling code for Maldives, ISBN Group Identifier for books published in Greece
  • The number of possible starting positions for the chess variant Chess960
    • Chess960 also got its name from the number itself
• 961 = 31², the largest 3-digit perfect square, sum of three consecutive primes (313 + 317 + 331), sum of five consecutive primes (181 + 191 + 193 + 197 + 199), centered octagonal number[26]
  • country calling code for Lebanon, ISBN Group Identifier for books published in Slovenia
• 962 = 2 × 13 × 37, sphenic number, nontotient
  • country calling code for Jordan, one of two ISBN Group Identifiers for books published in Hong Kong
• 963 = 3² × 107, sum of the first twenty-four primes
  • country calling code for Syria, ISBN Group Identifier for books published in Hungary
• 964 = 2² × 241, sum of four consecutive primes (233 + 239 + 241 + 251), nontotient, totient sum for first 56 integers
  • country calling code for Iraq, ISBN Group Identifier for books published in Iran, happy number
• 965 = 5 × 193
  • country calling code for Kuwait, ISBN Group Identifier for books published in Israel
• 966 = 2 × 3 × 7 × 23, sum of eight consecutive primes (103 + 107 + 109 + 113 + 127 + 131 + 137 + 139), Harshad number
  • country calling code for Saudi Arabia, one of two ISBN Group Identifiers for books published in Ukraine
• 967 = prime number
  • country calling code for Yemen, one of two ISBN Group Identifiers for books published in Malaysia
• 968 = 2³ × 11², nontotient
  • country calling code for Oman, one of two ISBN Group Identifiers for books published in Mexico
• 969 = 3 × 17 × 19, sphenic number, nonagonal number,[27] tetrahedral number[28]
  • ISBN Group Identifier for books published in Pakistan, age of Methuselah according to Old Testament, anti-Muslim movement in Myanmar

970s

• 970 = 2 × 5 × 97, sphenic number
  • country calling code for Palestinian territories, one of two ISBN Group Identifiers for books published in Mexico
• 971 = prime number, Chen prime, Eisenstein prime with no imaginary part
  • country calling code for United Arab Emirates, ISBN Group Identifier for books published in the Philippines
• 972 = 2² × 3⁵, Harshad number
  • country calling code for Israel, one of two ISBN Group Identifiers for books published in Portugal
• 973 = 7 × 139, happy number
  • country calling code for Bahrain, ISBN Group Identifier for books published in Romania,
• 974 = 2 × 487, nontotient
  • country calling code for Qatar, ISBN Group Identifier for books published in Thailand
• 975 = 3 × 5² × 13
  • country calling code for Bhutan, ISBN Group Identifier for books published in Turkey
• 976 = 2⁴ × 61, decagonal number[29]
  • country calling code for Mongolia, ISBN Group Identifier for books published in Antigua, Bahamas, Barbados, Belize, Cayman Islands, Dominica, Grenada, Guyana, Jamaica, Montserrat, Saint Kitts and Nevis, St. Lucia, St. Vincent and the Grenadines, Trinidad and Tobago, and the British Virgin Islands
• 977 = prime number, sum of nine consecutive primes (89 + 97 + 101 + 103 + 107 + 109 + 113 + 127 + 131), balanced prime,[21] Chen prime, Eisenstein prime with no imaginary part, Stern prime,[30] strictly non-palindromic number[31]
  • country calling code for Nepal
  • EAN prefix for ISSNs
  • ISBN Group Identifier for books published in Egypt
• 978 = 2 × 3 × 163, sphenic number, nontotient,
  • First EAN prefix for ISBNs
  • ISBN Group Identifier for books published in Nigeria
• 979 = 11 × 89
  • Second EAN prefix for ISBNs. Also for ISMNs
  • ISBN Group Identifier for books published in Indonesia

980s

• 980 = 2² × 5 × 7²
  • ISBN Group Identifier for books published in Venezuela
• 981 = 3² × 109
  • one of two ISBN Group Identifiers for books published in Singapore
• 982 = 2 × 491, happy number
  • ISBN Group Identifier for books published in the Cook Islands, Fiji, Kiribati, Marshall Islands, Micronesia, Nauru, New Caledonia, Niue, Palau, Solomon Islands, Tokelau, Tonga, Tuvalu, Vanuatu, Western Samoa
• 983 = prime number, safe prime,[32] Chen prime, Eisenstein prime with no imaginary part, Wedderburn–Etherington number,[33] strictly non-palindromic number[31]
  • One of two ISBN Group Identifiers for books published in Malaysia
• 984 = 2³ × 3 × 41
  • ISBN Group Identifier for books published in Bangladesh
• 985 = 5 × 197, sum of three consecutive primes (317 + 331 + 337), Markov number,[34] Pell number,[35] Smith number[2]
  • one of two ISBN Group Identifiers for books published in Belarus
• 986 = 2 × 17 × 29, sphenic number, nontotient
  • one of two ISBN Group Identifiers for books published in Taiwan and China
• 987 = 3 × 7 × 47, Fibonacci number[36]
  • one of two ISBN Group Identifiers for books published in Argentina
• 988 = 2² × 13 × 19, nontotient. sum of four consecutive primes (239 + 241 + 251 + 257)
  • one of two ISBN Group Identifiers for books published in Hong Kong
• 989 = 23 × 43, Extra strong Lucas pseudoprime[37]
  • one of two ISBN Group Identifiers for books published in Portugal

990s

• 990 = 2 × 3² × 5 × 11, sum of six consecutive primes (151 + 157 + 163 + 167 + 173 + 179), triangular number,[1] Harshad number
  • best possible VantageScore credit score
• 991 = prime number, sum of five consecutive primes (191 + 193 + 197 + 199 + 211), sum of seven consecutive primes (127 + 131 + 137 + 139 + 149 + 151 + 157), Chen prime
• 992 = 2⁵ × 31, pronic number,[11] nontotient; number of eleven-dimensional exotic spheres.[38]
  • country calling code for Tajikistan
• 993 = 3 × 331
  • country calling code for Turkmenistan
• 994 = 2 × 7 × 71, sphenic number, nontotient
  • country calling code for Azerbaijan
• 995 = 5 × 199
  • country calling code for Georgia
  • Singapore fire brigade and emergency ambulance services hotline
• 996 = 2² × 3 × 83
  • country calling code for Kyrgyzstan
• 997 = largest three-digit prime number, strictly non-palindromic number[31]
• 998 = 2 × 499, nontotient
  • country calling code for Uzbekistan

• 999 = 3³ × 37, Kaprekar number,[39] Harshad number
  • In some parts of the world, such as the UK and Commonwealth countries, 999 (pronounced as 9-9-9) is the emergency telephone number.
  • 999 was a London punk band active during the 1970s.

References

1. "Sloane's A000217 : Triangular numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
2. "Sloane's A006753 : Smith numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
3. "Sloane's A005282 : Mian-Chowla sequence". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
4. "Sloane's A002407 : Cuban primes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
5. "Sloane's A003215 : Hex (or centered hexagonal) numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
6. "Sloane's A000984 : Central binomial coefficients". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
7. "Sloane's A000326 : Pentagonal numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
8. "Sloane's A001844 : Centered square numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
9. "Sloane's A000073 : Tribonacci numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
10. "Sloane's A080076 : Proth primes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
11. "Sloane's A002378 : Oblong (or promic, pronic, or heteromecic) numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
12. "Sloane's A006972 : Lucas-Carmichael numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
13. "Sloane's A002411 : Pentagonal pyramidal numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
14. "Sloane's A003154 : Centered 12-gonal numbers. Also star numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
15. "Sloane's A006882 : Double factorials". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
16. Higgins, Peter (2008). Number Story: From Counting to Cryptography. New York: Copernicus. p. 13. ISBN 978-1-84800-000-1.
17. "Sloane's A006038 : Odd primitive abundant numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
18. "Sloane's A006036 : Primitive pseudoperfect numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
19. "Sloane's A076980 : Leyland numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
20. "Sloane's A000384 : Hexagonal numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
21. "Sloane's A006562 : Balanced primes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
22. "Sloane's A005891 : Centered pentagonal numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
23. "Sloane's A005384 : Sophie Germain primes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
24. "Sloane's A069099 : Centered heptagonal numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
25. "Sloane's A093112 : a(n) = (2^n-1)^2 - 2". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
26. "Sloane's A016754 : Odd squares: a(n) = (2n+1)^2. Also centered octagonal numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
27. "Sloane's A001106 : 9-gonal (or enneagonal or nonagonal) numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
28. "Sloane's A000292 : Tetrahedral numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
29. "Sloane's A001107 : 10-gonal (or decagonal) numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
30. "Sloane's A042978 : Stern primes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
31. "Sloane's A016038 : Strictly non-palindromic numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
32. "Sloane's A005385 : Safe primes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
33. "Sloane's A001190 : Wedderburn-Etherington numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
34. "Sloane's A002559 : Markoff (or Markov) numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
35. "Sloane's A000129 : Pell numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
36. "Sloane's A000045 : Fibonacci numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
37. "Sloane's A0217719 : Extra strong Lucas pseudoprimes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
38. "week164". Math.ucr.edu. 2001-01-13. Retrieved 2014-05-12.
39. "Sloane's A006886 : Kaprekar numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-02.