668904163 has 2 divisors, whose sum is σ = 668904164. Its totient is φ = 668904162.

The previous prime is 668904161. The next prime is 668904211. The reversal of 668904163 is 361409866.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 668904163 - 2¹ = 668904161 is a prime.

Together with 668904161, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (668904161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334452081 + 334452082.

It is an arithmetic number, because the mean of its divisors is an integer number (334452082).

Almost surely, 2^668904163 is an apocalyptic number.

668904163 is a deficient number, since it is larger than the sum of its proper divisors (1).

668904163 is an equidigital number, since it uses as much as digits as its factorization.

668904163 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 186624, while the sum is 43.

The square root of 668904163 is about 25863.1816101577. The cubic root of 668904163 is about 874.5566899427.

The spelling of 668904163 in words is "six hundred sixty-eight million, nine hundred four thousand, one hundred sixty-three".