12641256531 has 24 divisors (see below), whose sum is σ = 18510036480. Its totient is φ = 8312685696.

The previous prime is 12641256521. The next prime is 12641256541. The reversal of 12641256531 is 13565214621.

12641256531 is a `hidden beast` number, since 1 + 2 + 64 + 1 + 2 + 565 + 31 = 666.

12641256531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (12641256521) and next prime (12641256541).

It is a de Polignac number, because none of the positive numbers 2^k-12641256531 is a prime.

It is a super-2 number, since 2×12641256531² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (12641256521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 165775 + ... + 229703.

It is an arithmetic number, because the mean of its divisors is an integer number (771251520).

Almost surely, 2^12641256531 is an apocalyptic number.

12641256531 is a deficient number, since it is larger than the sum of its proper divisors (5868779949).

12641256531 is a wasteful number, since it uses less digits than its factorization.

12641256531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64235 (or 64232 counting only the distinct ones).

The product of its digits is 43200, while the sum is 36.

The spelling of 12641256531 in words is "twelve billion, six hundred forty-one million, two hundred fifty-six thousand, five hundred thirty-one".