656747656 has 8 divisors (see below), whose sum is σ = 1231401870. Its totient is φ = 328373824.

The previous prime is 656747653. The next prime is 656747683.

656747656 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in only one way, i.e., 623500900 + 33246756 = 24970^2 + 5766^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×656747656² = 862634967322988672, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is not an unprimeable number, because it can be changed into a prime (656747653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41046721 + ... + 41046736.

Almost surely, 2^656747656 is an apocalyptic number.

It is an amenable number.

656747656 is a deficient number, since it is larger than the sum of its proper divisors (574654214).

656747656 is a wasteful number, since it uses less digits than its factorization.

656747656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82093463 (or 82093459 counting only the distinct ones).

The product of its digits is 6350400, while the sum is 52.

The square root of 656747656 is about 25627.0883246615. The cubic root of 656747656 is about 869.2262711808.

The spelling of 656747656 in words is "six hundred fifty-six million, seven hundred forty-seven thousand, six hundred fifty-six".