660021978179 has 2 divisors, whose sum is σ = 660021978180. Its totient is φ = 660021978178.

The previous prime is 660021978157. The next prime is 660021978223. The reversal of 660021978179 is 971879120066.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-660021978179 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (660021978149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330010989089 + 330010989090.

It is an arithmetic number, because the mean of its divisors is an integer number (330010989090).

Almost surely, 2^660021978179 is an apocalyptic number.

660021978179 is a deficient number, since it is larger than the sum of its proper divisors (1).

660021978179 is an equidigital number, since it uses as much as digits as its factorization.

660021978179 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2286144, while the sum is 56.

The spelling of 660021978179 in words is "six hundred sixty billion, twenty-one million, nine hundred seventy-eight thousand, one hundred seventy-nine".