686704 has 20 divisors (see below), whose sum is σ = 1343664. Its totient is φ = 339968.

The previous prime is 686687. The next prime is 686723. The reversal of 686704 is 407686.

686704 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

686704 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2544 + ... + 2800.

2⁶⁸⁶⁷⁰⁴ is an apocalyptic number.

It is an amenable number.

686704 is a deficient number, since it is larger than the sum of its proper divisors (656960).

686704 is a wasteful number, since it uses less digits than its factorization.

686704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432 (or 426 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 686704 is about 828.6760525079. The cubic root of 686704 is about 88.2246327162.

The spelling of 686704 in words is "six hundred eighty-six thousand, seven hundred four".