680396657 has 2 divisors, whose sum is σ = 680396658. Its totient is φ = 680396656.

The previous prime is 680396641. The next prime is 680396671. The reversal of 680396657 is 756693086.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 542004961 + 138391696 = 23281^2 + 11764^2 .

It is a cyclic number.

It is not a de Polignac number, because 680396657 - 2⁴ = 680396641 is a prime.

It is a super-2 number, since 2×680396657² = 925879221713551298, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (680396357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340198328 + 340198329.

It is an arithmetic number, because the mean of its divisors is an integer number (340198329).

Almost surely, 2^680396657 is an apocalyptic number.

It is an amenable number.

680396657 is a deficient number, since it is larger than the sum of its proper divisors (1).

680396657 is an equidigital number, since it uses as much as digits as its factorization.

680396657 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1632960, while the sum is 50.

The square root of 680396657 is about 26084.4140628077. The cubic root of 680396657 is about 879.5368848500.

The spelling of 680396657 in words is "six hundred eighty million, three hundred ninety-six thousand, six hundred fifty-seven".