12661550631 has 12 divisors (see below), whose sum is σ = 18384662400. Its totient is φ = 8396838720.

The previous prime is 12661550621. The next prime is 12661550633. The reversal of 12661550631 is 13605516621.

12661550631 is a `hidden beast` number, since 1 + 2 + 6 + 6 + 15 + 5 + 0 + 631 = 666.

It is not a de Polignac number, because 12661550631 - 2⁵ = 12661550599 is a prime.

It is a super-2 number, since 2×12661550631² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12661550633) 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, 3681106 + ... + 3684543.

It is an arithmetic number, because the mean of its divisors is an integer number (1532055200).

Almost surely, 2^12661550631 is an apocalyptic number.

12661550631 is a deficient number, since it is larger than the sum of its proper divisors (5723111769).

12661550631 is a wasteful number, since it uses less digits than its factorization.

12661550631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7365846 (or 7365843 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The spelling of 12661550631 in words is "twelve billion, six hundred sixty-one million, five hundred fifty thousand, six hundred thirty-one".