31923931 has 24 divisors (see below), whose sum is σ = 37103616. Its totient is φ = 27387360.

The previous prime is 31923929. The next prime is 31923989. The reversal of 31923931 is 13932913.

It is not a de Polignac number, because 31923931 - 2¹ = 31923929 is a prime.

It is a super-2 number, since 2×31923931² = 2038274740985522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31923893 and 31923902.

It is not an unprimeable number, because it can be changed into a prime (31923911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 167046 + ... + 167236.

It is an arithmetic number, because the mean of its divisors is an integer number (1545984).

Almost surely, 2^31923931 is an apocalyptic number.

31923931 is a deficient number, since it is larger than the sum of its proper divisors (5179685).

31923931 is a wasteful number, since it uses less digits than its factorization.

31923931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 283 (or 270 counting only the distinct ones).

The product of its digits is 4374, while the sum is 31.

The square root of 31923931 is about 5650.1266357490. The cubic root of 31923931 is about 317.2284441034.

The spelling of 31923931 in words is "thirty-one million, nine hundred twenty-three thousand, nine hundred thirty-one".