56691819664 has 20 divisors (see below), whose sum is σ = 110008629756. Its totient is φ = 28302495872.

The previous prime is 56691819659. The next prime is 56691819683. The reversal of 56691819664 is 46691819665.

It can be written as a sum of positive squares in 2 ways, for example, as 20822490000 + 35869329664 = 144300^2 + 189392^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2702599 + ... + 2723494.

Almost surely, 2^56691819664 is an apocalyptic number.

It is an amenable number.

56691819664 is a deficient number, since it is larger than the sum of its proper divisors (53316810092).

56691819664 is a wasteful number, since it uses less digits than its factorization.

56691819664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5426754 (or 5426748 counting only the distinct ones).

The product of its digits is 16796160, while the sum is 61.

Subtracting from 56691819664 its reverse (46691819665), we obtain a palindrome (9999999999).

The spelling of 56691819664 in words is "fifty-six billion, six hundred ninety-one million, eight hundred nineteen thousand, six hundred sixty-four".