31131301931 has 2 divisors, whose sum is σ = 31131301932. Its totient is φ = 31131301930.

The previous prime is 31131301919. The next prime is 31131301967. The reversal of 31131301931 is 13910313113.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31131301931 is a prime.

It is a super-2 number, since 2×31131301931² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 31131301931.

It is not a weakly prime, because it can be changed into another prime (31131301231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15565650965 + 15565650966.

It is an arithmetic number, because the mean of its divisors is an integer number (15565650966).

Almost surely, 2^31131301931 is an apocalyptic number.

31131301931 is a deficient number, since it is larger than the sum of its proper divisors (1).

31131301931 is an equidigital number, since it uses as much as digits as its factorization.

31131301931 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 729, while the sum is 26.

The spelling of 31131301931 in words is "thirty-one billion, one hundred thirty-one million, three hundred one thousand, nine hundred thirty-one".