669670879 has 2 divisors, whose sum is σ = 669670880. Its totient is φ = 669670878.

The previous prime is 669670867. The next prime is 669670889. The reversal of 669670879 is 978076966.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 669670879 - 2¹⁵ = 669638111 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (669670819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334835439 + 334835440.

It is an arithmetic number, because the mean of its divisors is an integer number (334835440).

Almost surely, 2^669670879 is an apocalyptic number.

669670879 is a deficient number, since it is larger than the sum of its proper divisors (1).

669670879 is an equidigital number, since it uses as much as digits as its factorization.

669670879 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6858432, while the sum is 58.

The square root of 669670879 is about 25877.9999033928. Note that the first 4 decimals coincide. The cubic root of 669670879 is about 874.8907091797.

The spelling of 669670879 in words is "six hundred sixty-nine million, six hundred seventy thousand, eight hundred seventy-nine".