56165644021 has 12 divisors (see below), whose sum is σ = 59817347460. Its totient is φ = 52725785600.

The previous prime is 56165643979. The next prime is 56165644057. The reversal of 56165644021 is 12044656165.

It can be written as a sum of positive squares in 6 ways, for example, as 1121915025 + 55043728996 = 33495^2 + 234614^2 .

It is not a de Polignac number, because 56165644021 - 2²⁵ = 56132089589 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56165644061) 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 11 ways as a sum of consecutive naturals, for example, 137380 + ... + 362221.

It is an arithmetic number, because the mean of its divisors is an integer number (4984778955).

Almost surely, 2^56165644021 is an apocalyptic number.

It is an amenable number.

56165644021 is a deficient number, since it is larger than the sum of its proper divisors (3651703439).

56165644021 is a wasteful number, since it uses less digits than its factorization.

56165644021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500024 (or 500007 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 40.

The spelling of 56165644021 in words is "fifty-six billion, one hundred sixty-five million, six hundred forty-four thousand, twenty-one".