31165893981 has 12 divisors (see below), whose sum is σ = 45062568252. Its totient is φ = 20756416896.

The previous prime is 31165893953. The next prime is 31165894043. The reversal of 31165893981 is 18939856113.

It can be written as a sum of positive squares in 2 ways, for example, as 28752628356 + 2413265625 = 169566^2 + 49125^2 .

It is not a de Polignac number, because 31165893981 - 2⁹ = 31165893469 is a prime.

It is a super-2 number, since 2×31165893981² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31165893911) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1727676 + ... + 1745621.

It is an arithmetic number, because the mean of its divisors is an integer number (3755214021).

Almost surely, 2^31165893981 is an apocalyptic number.

It is an amenable number.

31165893981 is a deficient number, since it is larger than the sum of its proper divisors (13896674271).

31165893981 is a wasteful number, since it uses less digits than its factorization.

31165893981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3474300 (or 3474297 counting only the distinct ones).

The product of its digits is 1399680, while the sum is 54.

The spelling of 31165893981 in words is "thirty-one billion, one hundred sixty-five million, eight hundred ninety-three thousand, nine hundred eighty-one".