680344921 has 2 divisors, whose sum is σ = 680344922. Its totient is φ = 680344920.

The previous prime is 680344897. The next prime is 680344927. The reversal of 680344921 is 129443086.

680344921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 443523600 + 236821321 = 21060^2 + 15389^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-680344921 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (680344927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340172460 + 340172461.

It is an arithmetic number, because the mean of its divisors is an integer number (340172461).

Almost surely, 2^680344921 is an apocalyptic number.

It is an amenable number.

680344921 is a deficient number, since it is larger than the sum of its proper divisors (1).

680344921 is an equidigital number, since it uses as much as digits as its factorization.

680344921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 41472, while the sum is 37.

The square root of 680344921 is about 26083.4223406362. The cubic root of 680344921 is about 879.5145915435.

The spelling of 680344921 in words is "six hundred eighty million, three hundred forty-four thousand, nine hundred twenty-one".