656307997 has 2 divisors, whose sum is σ = 656307998. Its totient is φ = 656307996.

The previous prime is 656307959. The next prime is 656308007. The reversal of 656307997 is 799703656.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 642064921 + 14243076 = 25339^2 + 3774^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-656307997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (656307907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328153998 + 328153999.

It is an arithmetic number, because the mean of its divisors is an integer number (328153999).

Almost surely, 2^656307997 is an apocalyptic number.

It is an amenable number.

656307997 is a deficient number, since it is larger than the sum of its proper divisors (1).

656307997 is an equidigital number, since it uses as much as digits as its factorization.

656307997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2143260, while the sum is 52.

The square root of 656307997 is about 25618.5088754205. The cubic root of 656307997 is about 869.0322603554.

The spelling of 656307997 in words is "six hundred fifty-six million, three hundred seven thousand, nine hundred ninety-seven".