31607928 has 128 divisors (see below), whose sum is σ = 97977600. Its totient is φ = 9360000.

The previous prime is 31607921. The next prime is 31607969. The reversal of 31607928 is 82970613.

It is a super-2 number, since 2×31607928² = 1998122224906368, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 31607892 and 31607901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31607921) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 125803 + ... + 126053.

It is an arithmetic number, because the mean of its divisors is an integer number (765450).

Almost surely, 2^31607928 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31607928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48988800).

31607928 is an abundant number, since it is smaller than the sum of its proper divisors (66369672).

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

31607928 is a wasteful number, since it uses less digits than its factorization.

31607928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330 (or 320 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 31607928 is about 5622.0928487530. The cubic root of 31607928 is about 316.1782629290.

The spelling of 31607928 in words is "thirty-one million, six hundred seven thousand, nine hundred twenty-eight".