656662544957 has 4 divisors (see below), whose sum is σ = 679306081020. Its totient is φ = 634019008896.

The previous prime is 656662544939. The next prime is 656662544983. The reversal of 656662544957 is 759445266656.

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 296073103876 + 360589441081 = 544126^2 + 600491^2 .

It is a cyclic number.

It is not a de Polignac number, because 656662544957 - 2¹² = 656662540861 is a prime.

It is a super-2 number, since 2×656662544957² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 656662544893 and 656662544902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656662544917) 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, 11321767988 + ... + 11321768045.

It is an arithmetic number, because the mean of its divisors is an integer number (169826520255).

Almost surely, 2^656662544957 is an apocalyptic number.

It is an amenable number.

656662544957 is a deficient number, since it is larger than the sum of its proper divisors (22643536063).

656662544957 is a wasteful number, since it uses less digits than its factorization.

656662544957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22643536062.

The product of its digits is 326592000, while the sum is 65.

The spelling of 656662544957 in words is "six hundred fifty-six billion, six hundred sixty-two million, five hundred forty-four thousand, nine hundred fifty-seven".