679940 has 12 divisors (see below), whose sum is σ = 1427916. Its totient is φ = 271968.

The previous prime is 679933. The next prime is 679951. The reversal of 679940 is 49976.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 329476 + 350464 = 574^2 + 592^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 679940.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16979 + ... + 17018.

It is an arithmetic number, because the mean of its divisors is an integer number (118993).

2⁶⁷⁹⁹⁴⁰ is an apocalyptic number.

It is an amenable number.

679940 is an abundant number, since it is smaller than the sum of its proper divisors (747976).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

679940 is a wasteful number, since it uses less digits than its factorization.

679940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34006 (or 34004 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 679940 is about 824.5847439772. The cubic root of 679940 is about 87.9340069967.

The spelling of 679940 in words is "six hundred seventy-nine thousand, nine hundred forty".