679988 has 12 divisors (see below), whose sum is σ = 1199520. Its totient is φ = 337272.

The previous prime is 679981. The next prime is 679993. The reversal of 679988 is 889976.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 679988.

It is not an unprimeable number, because it can be changed into a prime (679981) by changing a digit.

679988 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56 + ... + 1167.

It is an arithmetic number, because the mean of its divisors is an integer number (99960).

2⁶⁷⁹⁹⁸⁸ is an apocalyptic number.

It is an amenable number.

679988 is a deficient number, since it is larger than the sum of its proper divisors (519532).

679988 is a wasteful number, since it uses less digits than its factorization.

679988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1366 (or 1364 counting only the distinct ones).

The product of its digits is 217728, while the sum is 47.

The square root of 679988 is about 824.6138490227. The cubic root of 679988 is about 87.9360761660.

The spelling of 679988 in words is "six hundred seventy-nine thousand, nine hundred eighty-eight".