686680 has 16 divisors (see below), whose sum is σ = 1545120. Its totient is φ = 274656.

The previous prime is 686671. The next prime is 686687. The reversal of 686680 is 86686.

It is a happy number.

686680 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 not an unprimeable number, because it can be changed into a prime (686687) 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, 8544 + ... + 8623.

It is an arithmetic number, because the mean of its divisors is an integer number (96570).

2⁶⁸⁶⁶⁸⁰ is an apocalyptic number.

It is an amenable number.

686680 is an abundant number, since it is smaller than the sum of its proper divisors (858440).

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

686680 is a wasteful number, since it uses less digits than its factorization.

686680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17178 (or 17174 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 34.

The square root of 686680 is about 828.6615714512. The cubic root of 686680 is about 88.2236049003.

The spelling of 686680 in words is "six hundred eighty-six thousand, six hundred eighty".