656023681 has 2 divisors, whose sum is σ = 656023682. Its totient is φ = 656023680.

The previous prime is 656023651. The next prime is 656023699. The reversal of 656023681 is 186320656.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 565678656 + 90345025 = 23784^2 + 9505^2 .

It is a cyclic number.

It is not a de Polignac number, because 656023681 - 2⁷ = 656023553 is a prime.

It is a super-2 number, since 2×656023681² = 860734140065579522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 656023681.

It is not a weakly prime, because it can be changed into another prime (656023631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328011840 + 328011841.

It is an arithmetic number, because the mean of its divisors is an integer number (328011841).

Almost surely, 2^656023681 is an apocalyptic number.

It is an amenable number.

656023681 is a deficient number, since it is larger than the sum of its proper divisors (1).

656023681 is an equidigital number, since it uses as much as digits as its factorization.

656023681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 51840, while the sum is 37.

The square root of 656023681 is about 25612.9592394163. The cubic root of 656023681 is about 868.9067524818.

The spelling of 656023681 in words is "six hundred fifty-six million, twenty-three thousand, six hundred eighty-one".