31881404 has 24 divisors (see below), whose sum is σ = 59579520. Its totient is φ = 14891184.

The previous prime is 31881403. The next prime is 31881413. The reversal of 31881404 is 40418813.

It is a super-2 number, since 2×31881404² = 2032847842022432, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31881401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 74 + ... + 7985.

It is an arithmetic number, because the mean of its divisors is an integer number (2482480).

Almost surely, 2^31881404 is an apocalyptic number.

It is an amenable number.

31881404 is a deficient number, since it is larger than the sum of its proper divisors (27698116).

31881404 is a wasteful number, since it uses less digits than its factorization.

31881404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8129 (or 8127 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 29.

The square root of 31881404 is about 5646.3620146073. The cubic root of 31881404 is about 317.0875177558.

The spelling of 31881404 in words is "thirty-one million, eight hundred eighty-one thousand, four hundred four".