656764773866 has 4 divisors (see below), whose sum is σ = 985147160802. Its totient is φ = 328382386932.

The previous prime is 656764773859. The next prime is 656764773913. The reversal of 656764773866 is 668377467656.

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

It can be written as a sum of positive squares in only one way, i.e., 632653206025 + 24111567841 = 795395^2 + 155279^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 656764773866.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 164191193465 + ... + 164191193468.

Almost surely, 2^656764773866 is an apocalyptic number.

656764773866 is a deficient number, since it is larger than the sum of its proper divisors (328382386936).

656764773866 is a wasteful number, since it uses less digits than its factorization.

656764773866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 328382386935.

The product of its digits is 1280240640, while the sum is 71.

The spelling of 656764773866 in words is "six hundred fifty-six billion, seven hundred sixty-four million, seven hundred seventy-three thousand, eight hundred sixty-six".