680672309 has 2 divisors, whose sum is σ = 680672310. Its totient is φ = 680672308.

The previous prime is 680672249. The next prime is 680672323. The reversal of 680672309 is 903276086.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 465610084 + 215062225 = 21578^2 + 14665^2 .

It is a cyclic number.

It is not a de Polignac number, because 680672309 - 2¹² = 680668213 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (680672329) 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, 340336154 + 340336155.

It is an arithmetic number, because the mean of its divisors is an integer number (340336155).

Almost surely, 2^680672309 is an apocalyptic number.

It is an amenable number.

680672309 is a deficient number, since it is larger than the sum of its proper divisors (1).

680672309 is an equidigital number, since it uses as much as digits as its factorization.

680672309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 108864, while the sum is 41.

The square root of 680672309 is about 26089.6973727178. The cubic root of 680672309 is about 879.6556456568.

The spelling of 680672309 in words is "six hundred eighty million, six hundred seventy-two thousand, three hundred nine".