12566505256 has 8 divisors (see below), whose sum is σ = 23562197370. Its totient is φ = 6283252624.

The previous prime is 12566505181. The next prime is 12566505257. The reversal of 12566505256 is 65250566521.

It can be written as a sum of positive squares in only one way, i.e., 9962036100 + 2604469156 = 99810^2 + 51034^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (12566505257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 785406571 + ... + 785406586.

Almost surely, 2^12566505256 is an apocalyptic number.

It is an amenable number.

12566505256 is a deficient number, since it is larger than the sum of its proper divisors (10995692114).

12566505256 is a wasteful number, since it uses less digits than its factorization.

12566505256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1570813163 (or 1570813159 counting only the distinct ones).

The product of its (nonzero) digits is 540000, while the sum is 43.

The spelling of 12566505256 in words is "twelve billion, five hundred sixty-six million, five hundred five thousand, two hundred fifty-six".