31507660813 has 2 divisors, whose sum is σ = 31507660814. Its totient is φ = 31507660812.

The previous prime is 31507660799. The next prime is 31507660817. The reversal of 31507660813 is 31806670513.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30240514404 + 1267146409 = 173898^2 + 35597^2 .

It is a cyclic number.

It is not a de Polignac number, because 31507660813 - 2⁵ = 31507660781 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31507660817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15753830406 + 15753830407.

It is an arithmetic number, because the mean of its divisors is an integer number (15753830407).

Almost surely, 2^31507660813 is an apocalyptic number.

It is an amenable number.

31507660813 is a deficient number, since it is larger than the sum of its proper divisors (1).

31507660813 is an equidigital number, since it uses as much as digits as its factorization.

31507660813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 90720, while the sum is 40.

It can be divided in two parts, 315076608 and 13, that multiplied together give a palindrome (4095995904).

The spelling of 31507660813 in words is "thirty-one billion, five hundred seven million, six hundred sixty thousand, eight hundred thirteen".