56637708721 has 4 divisors (see below), whose sum is σ = 61786591344. Its totient is φ = 51488826100.

The previous prime is 56637708713. The next prime is 56637708733. The reversal of 56637708721 is 12780773665.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 56637708721 - 2³ = 56637708713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (56637738721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2574441295 + ... + 2574441316.

It is an arithmetic number, because the mean of its divisors is an integer number (15446647836).

Almost surely, 2^56637708721 is an apocalyptic number.

It is an amenable number.

56637708721 is a deficient number, since it is larger than the sum of its proper divisors (5148882623).

56637708721 is a wasteful number, since it uses less digits than its factorization.

56637708721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5148882622.

The product of its (nonzero) digits is 2963520, while the sum is 52.

The spelling of 56637708721 in words is "fifty-six billion, six hundred thirty-seven million, seven hundred eight thousand, seven hundred twenty-one".