12566861613 has 8 divisors (see below), whose sum is σ = 18617572800. Its totient is φ = 8377907724.

The previous prime is 12566861609. The next prime is 12566861627. The reversal of 12566861613 is 31616866521.

12566861613 is a `hidden beast` number, since 1 + 2 + 566 + 86 + 1 + 6 + 1 + 3 = 666.

It is not a de Polignac number, because 12566861613 - 2² = 12566861609 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12566861603) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 232719633 + ... + 232719686.

It is an arithmetic number, because the mean of its divisors is an integer number (2327196600).

Almost surely, 2^12566861613 is an apocalyptic number.

It is an amenable number.

12566861613 is a deficient number, since it is larger than the sum of its proper divisors (6050711187).

12566861613 is an equidigital number, since it uses as much as digits as its factorization.

12566861613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 465439328 (or 465439322 counting only the distinct ones).

The product of its digits is 311040, while the sum is 45.

The spelling of 12566861613 in words is "twelve billion, five hundred sixty-six million, eight hundred sixty-one thousand, six hundred thirteen".