656647668713 has 4 divisors (see below), whose sum is σ = 656680356228. Its totient is φ = 656614981200.

The previous prime is 656647668707. The next prime is 656647668727. The reversal of 656647668713 is 317866746656.

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 244898296384 + 411749372329 = 494872^2 + 641677^2 .

It is a cyclic number.

It is not a de Polignac number, because 656647668713 - 2²⁰ = 656646620137 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 656647668713.

It is not an unprimeable number, because it can be changed into a prime (656647668113) by changing a digit.

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, 16313606 + ... + 16353807.

It is an arithmetic number, because the mean of its divisors is an integer number (164170089057).

Almost surely, 2^656647668713 is an apocalyptic number.

It is an amenable number.

656647668713 is a deficient number, since it is larger than the sum of its proper divisors (32687515).

656647668713 is a wasteful number, since it uses less digits than its factorization.

656647668713 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32687514.

The product of its digits is 182891520, while the sum is 65.

It can be divided in two parts, 65664 and 7668713, that added together give a palindrome (7734377).

The spelling of 656647668713 in words is "six hundred fifty-six billion, six hundred forty-seven million, six hundred sixty-eight thousand, seven hundred thirteen".