12639958731 has 6 divisors (see below), whose sum is σ = 18257718180. Its totient is φ = 8426639148.

The previous prime is 12639958691. The next prime is 12639958733. The reversal of 12639958731 is 13785993621.

12639958731 is a `hidden beast` number, since 1 + 26 + 3 + 9 + 9 + 587 + 31 = 666.

It is not a de Polignac number, because 12639958731 - 2³¹ = 10492475083 is a prime.

It is a super-2 number, since 2×12639958731² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (12639958733) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 702219921 + ... + 702219938.

It is an arithmetic number, because the mean of its divisors is an integer number (3042953030).

Almost surely, 2^12639958731 is an apocalyptic number.

12639958731 is a deficient number, since it is larger than the sum of its proper divisors (5617759449).

12639958731 is a wasteful number, since it uses less digits than its factorization.

12639958731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1404439865 (or 1404439862 counting only the distinct ones).

The product of its digits is 2449440, while the sum is 54.

The spelling of 12639958731 in words is "twelve billion, six hundred thirty-nine million, nine hundred fifty-eight thousand, seven hundred thirty-one".