679974989 has 2 divisors, whose sum is σ = 679974990. Its totient is φ = 679974988.

The previous prime is 679974979. The next prime is 679975057. The reversal of 679974989 is 989479976.

It is an a-pointer prime, because the next prime (679975057) can be obtained adding 679974989 to its sum of digits (68).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 572022889 + 107952100 = 23917^2 + 10390^2 .

It is a cyclic number.

It is not a de Polignac number, because 679974989 - 2²⁸ = 411539533 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a nialpdrome in base 14.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (679974949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339987494 + 339987495.

It is an arithmetic number, because the mean of its divisors is an integer number (339987495).

Almost surely, 2^679974989 is an apocalyptic number.

It is an amenable number.

679974989 is a deficient number, since it is larger than the sum of its proper divisors (1).

679974989 is an equidigital number, since it uses as much as digits as its factorization.

679974989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 61725888, while the sum is 68.

The square root of 679974989 is about 26076.3300523674. The cubic root of 679974989 is about 879.3551530145.

The spelling of 679974989 in words is "six hundred seventy-nine million, nine hundred seventy-four thousand, nine hundred eighty-nine".