31681904 has 30 divisors (see below), whose sum is σ = 62623224. Its totient is φ = 15524320.

The previous prime is 31681877. The next prime is 31681913. The reversal of 31681904 is 40918613.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 189629 + ... + 189795.

Almost surely, 2^31681904 is an apocalyptic number.

It is an amenable number.

31681904 is a deficient number, since it is larger than the sum of its proper divisors (30941320).

31681904 is an equidigital number, since it uses as much as digits as its factorization.

31681904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413 (or 240 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 31681904 is about 5628.6680484818. The cubic root of 31681904 is about 316.4247346334.

The spelling of 31681904 in words is "thirty-one million, six hundred eighty-one thousand, nine hundred four".