12731931 has 8 divisors (see below), whose sum is σ = 18862160. Its totient is φ = 8487936.

The previous prime is 12731923. The next prime is 12731941. The reversal of 12731931 is 13913721.

It is not a de Polignac number, because 12731931 - 2³ = 12731923 is a prime.

It is a super-2 number, since 2×12731931² = 324204133977522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 471553 = 12731931 / (1 + 2 + 7 + 3 + 1 + 9 + 3 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12731895 and 12731904.

It is not an unprimeable number, because it can be changed into a prime (12731911) 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, 235750 + ... + 235803.

It is an arithmetic number, because the mean of its divisors is an integer number (2357770).

Almost surely, 2^12731931 is an apocalyptic number.

12731931 is a deficient number, since it is larger than the sum of its proper divisors (6130229).

12731931 is an equidigital number, since it uses as much as digits as its factorization.

12731931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 471562 (or 471556 counting only the distinct ones).

The product of its digits is 1134, while the sum is 27.

The square root of 12731931 is about 3568.1831511289. The cubic root of 12731931 is about 233.5060256719.

The spelling of 12731931 in words is "twelve million, seven hundred thirty-one thousand, nine hundred thirty-one".