668138435099 has 2 divisors, whose sum is σ = 668138435100. Its totient is φ = 668138435098.

The previous prime is 668138435059. The next prime is 668138435101. The reversal of 668138435099 is 990534831866.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-668138435099 is a prime.

Together with 668138435101, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (668138435059) 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, 334069217549 + 334069217550.

It is an arithmetic number, because the mean of its divisors is an integer number (334069217550).

Almost surely, 2^668138435099 is an apocalyptic number.

668138435099 is a deficient number, since it is larger than the sum of its proper divisors (1).

668138435099 is an equidigital number, since it uses as much as digits as its factorization.

668138435099 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 33592320, while the sum is 62.

The spelling of 668138435099 in words is "six hundred sixty-eight billion, one hundred thirty-eight million, four hundred thirty-five thousand, ninety-nine".