31993904 has 10 divisors (see below), whose sum is σ = 61988220. Its totient is φ = 15996944.

The previous prime is 31993901. The next prime is 31993909. The reversal of 31993904 is 40939913.

It is a super-2 number, since 2×31993904² = 2047219786322432, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (31993901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 999794 + ... + 999825.

It is an arithmetic number, because the mean of its divisors is an integer number (6198822).

Almost surely, 2^31993904 is an apocalyptic number.

It is an amenable number.

31993904 is a deficient number, since it is larger than the sum of its proper divisors (29994316).

31993904 is a wasteful number, since it uses less digits than its factorization.

31993904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1999627 (or 1999621 counting only the distinct ones).

The product of its (nonzero) digits is 26244, while the sum is 38.

The square root of 31993904 is about 5656.3154084616. The cubic root of 31993904 is about 317.4600491200.

The spelling of 31993904 in words is "thirty-one million, nine hundred ninety-three thousand, nine hundred four".