686856 has 16 divisors (see below), whose sum is σ = 1717200. Its totient is φ = 228944.

The previous prime is 686843. The next prime is 686863. The reversal of 686856 is 658686.

It is an unprimeable number.

686856 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, 14286 + ... + 14333.

It is an arithmetic number, because the mean of its divisors is an integer number (107325).

2⁶⁸⁶⁸⁵⁶ is an apocalyptic number.

It is an amenable number.

686856 is an abundant number, since it is smaller than the sum of its proper divisors (1030344).

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

686856 is a wasteful number, since it uses less digits than its factorization.

686856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28628 (or 28624 counting only the distinct ones).

The product of its digits is 69120, while the sum is 39.

The square root of 686856 is about 828.7677599907. The cubic root of 686856 is about 88.2311416608.

The spelling of 686856 in words is "six hundred eighty-six thousand, eight hundred fifty-six".