679639 has 2 divisors, whose sum is σ = 679640. Its totient is φ = 679638.

The previous prime is 679633. The next prime is 679669. The reversal of 679639 is 936976.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 679639 - 2⁵ = 679607 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (679633) 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, 339819 + 339820.

It is an arithmetic number, because the mean of its divisors is an integer number (339820).

2⁶⁷⁹⁶³⁹ is an apocalyptic number.

679639 is a deficient number, since it is larger than the sum of its proper divisors (1).

679639 is an equidigital number, since it uses as much as digits as its factorization.

679639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 61236, while the sum is 40.

The square root of 679639 is about 824.4022076632. The cubic root of 679639 is about 87.9210293601.

The spelling of 679639 in words is "six hundred seventy-nine thousand, six hundred thirty-nine".