# 900 (number)

(Redirected from 931 (number))
 ← 899 900 901 →
Cardinalnine hundred
Ordinal900th
(nine hundredth)
Factorization22 × 32 × 52
Divisors1, 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 numeralϠ´
Roman numeralCM
Unicode symbol(s)CM, cm
Binary11100001002
Ternary10201003
Octal16048
Duodecimal63012

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 positive integers. In base 10 it is a Harshad number.

900 is also:

## Integers from 901 to 999

### 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,[4] Mertens function(913) returns 0.
• 914 = 2 × 457, nontotient
• 915 = 3 × 5 × 61, sphenic number, Smith number,[4] Mertens function(915) returns 0, Harshad number
• 916 = 22 × 229, Mertens function(916) returns 0, nontotient, member of the Mian–Chowla sequence[5]
• 917 = 7 × 131, sum of five consecutive primes (173 + 179 + 181 + 191 + 193)
• 918 = 2 × 33 × 17, Harshad number
• 919 = prime number, cuban prime,[6] Chen prime, palindromic prime, centered hexagonal number,[7] Mertens function(919) returns 0

### 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,[17] smallest odd abundant number (divisors less than itself add up to 975);[18] smallest odd primitive abundant number;[19] smallest odd primitive semiperfect number;[20] Leyland number[21]
• 946 = 2 × 11 × 43, sphenic number, triangular number,[3] hexagonal number,[22] happy number
• 947 = prime number, sum of seven consecutive primes (113 + 127 + 131 + 137 + 139 + 149 + 151), balanced prime,[23] 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[24]
• 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,[25] Chen prime, Eisenstein prime with no imaginary part, centered heptagonal number[26]
• 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
• 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[4]
• 959 = 7 × 137
• 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[27]
• 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,[28] tetrahedral number[29]

### 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[30]
• 977 = prime number, sum of nine consecutive primes (89 + 97 + 101 + 103 + 107 + 109 + 113 + 127 + 131), balanced prime,[23] Chen prime, Eisenstein prime with no imaginary part, Stern prime,[31] strictly non-palindromic number[32]
• 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

### 990s

• 990 = 2 × 32 × 5 × 11, sum of six consecutive primes (151 + 157 + 163 + 167 + 173 + 179), triangular number,[3] Harshad number
• 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,[13] nontotient; number of eleven-dimensional exotic spheres.[39]
• 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[32]
• 998 = 2 × 499, nontotient
• country calling code for Uzbekistan

## References

1. ^ "Pay-Per-Call Information Services". Federal Communications Commission. 2011-02-11. Retrieved 2021-03-31.
2. ^ "Bowler throws 36 consecutive strikes for incredible 900 series". For The Win (in American English). 2016-01-13. Retrieved 2021-03-31.
3. ^ a b c "Sloane's A000217 : Triangular numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
4. "Sloane's A006753 : Smith numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
5. ^ "Sloane's A005282 : Mian-Chowla sequence". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
6. ^ "Sloane's A002407 : Cuban primes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
7. ^ "Sloane's A003215 : Hex (or centered hexagonal) numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
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18. ^ Higgins, Peter (2008). Number Story: From Counting to Cryptography. New York: Copernicus. p. 13. ISBN 978-1-84800-000-1.
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23. ^ a b "Sloane's A006562 : Balanced primes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
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25. ^ "Sloane's A005384 : Sophie Germain primes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
26. ^ "Sloane's A069099 : Centered heptagonal numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
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31. ^ "Sloane's A042978 : Stern primes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
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34. ^ "Sloane's A001190 : Wedderburn-Etherington numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
35. ^ "Sloane's A002559 : Markoff (or Markov) numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
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38. ^ "Sloane's A0217719 : Extra strong Lucas pseudoprimes". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-11.
39. ^ "week164". Math.ucr.edu. 2001-01-13. Retrieved 2014-05-12.
40. ^ "Sloane's A006886 : Kaprekar numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-02.