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BaseRepresentation
bin111100100100000
31120112110
413210200
51443013
6355320
7156255
oct74440
946473
1031008
112132a
1215b40
1311163
14b42c
1592c3
hex7920

31008 has 48 divisors (see below), whose sum is σ = 90720. Its totient is φ = 9216.

The previous prime is 30983. The next prime is 31013. The reversal of 31008 is 80013.

It is a tau number, because it is divible by the number of its divisors (48).

It is a super-2 number, since 2×310082 = 1922992128, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a nialpdrome in base 8.

It is a junction number, because it is equal to n+sod(n) for n = 30984 and 31002.

It is an unprimeable number.

31008 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1623 + ... + 1641.

It is an arithmetic number, because the mean of its divisors is an integer number (1890).

231008 is an apocalyptic number.

31008 is a gapful number since it is divisible by the number (38) formed by its first and last digit.

31008 is the 102-nd octagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45360).

31008 is an abundant number, since it is smaller than the sum of its proper divisors (59712).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31008 is a wasteful number, since it uses less digits than its factorization.

31008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49 (or 41 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 31008 is about 176.0908856244. The cubic root of 31008 is about 31.4165085544.

The spelling of 31008 in words is "thirty-one thousand, eight".