23556656637 has 6 divisors (see below), whose sum is σ = 34026281822. Its totient is φ = 15704437752.

The previous prime is 23556656623. The next prime is 23556656647. The reversal of 23556656637 is 73665665532.

23556656637 is a `hidden beast` number, since 2 + 3 + 556 + 6 + 56 + 6 + 37 = 666.

It can be written as a sum of positive squares in only one way, i.e., 17632121796 + 5924534841 = 132786^2 + 76971^2 .

It is not a de Polignac number, because 23556656637 - 2⁴ = 23556656621 is a prime.

It is a super-2 number, since 2×23556656637² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23556656647) 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, 1308703138 + ... + 1308703155.

Almost surely, 2^23556656637 is an apocalyptic number.

It is an amenable number.

23556656637 is a deficient number, since it is larger than the sum of its proper divisors (10469625185).

23556656637 is a wasteful number, since it uses less digits than its factorization.

23556656637 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2617406299 (or 2617406296 counting only the distinct ones).

The product of its digits is 20412000, while the sum is 54.

The spelling of 23556656637 in words is "twenty-three billion, five hundred fifty-six million, six hundred fifty-six thousand, six hundred thirty-seven".