679685 has 4 divisors (see below), whose sum is σ = 815628. Its totient is φ = 543744.

The previous prime is 679681. The next prime is 679691. The reversal of 679685 is 586976.

It is a happy number.

679685 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 401956 + 277729 = 634^2 + 527^2 .

It is a cyclic number.

It is not a de Polignac number, because 679685 - 2² = 679681 is a prime.

It is a Duffinian number.

It is a plaindrome in base 14.

It is a zygodrome in base 4.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (679681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67964 + ... + 67973.

It is an arithmetic number, because the mean of its divisors is an integer number (203907).

2⁶⁷⁹⁶⁸⁵ is an apocalyptic number.

It is an amenable number.

679685 is a deficient number, since it is larger than the sum of its proper divisors (135943).

679685 is a wasteful number, since it uses less digits than its factorization.

679685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135942.

The product of its digits is 90720, while the sum is 41.

The square root of 679685 is about 824.4301061946. The cubic root of 679685 is about 87.9230129014.

The spelling of 679685 in words is "six hundred seventy-nine thousand, six hundred eighty-five".