56712821765 has 4 divisors (see below), whose sum is σ = 68055386124. Its totient is φ = 45370257408.

The previous prime is 56712821731. The next prime is 56712821807.

56712821765 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 41851748929 + 14861072836 = 204577^2 + 121906^2 .

It is a cyclic number.

It is not a de Polignac number, because 56712821765 - 2¹⁰ = 56712820741 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5671282172 + ... + 5671282181.

It is an arithmetic number, because the mean of its divisors is an integer number (17013846531).

Almost surely, 2^56712821765 is an apocalyptic number.

It is an amenable number.

56712821765 is a deficient number, since it is larger than the sum of its proper divisors (11342564359).

56712821765 is a wasteful number, since it uses less digits than its factorization.

56712821765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11342564358.

The product of its digits is 1411200, while the sum is 50.

The spelling of 56712821765 in words is "fifty-six billion, seven hundred twelve million, eight hundred twenty-one thousand, seven hundred sixty-five".