685880 has 32 divisors (see below), whose sum is σ = 1663200. Its totient is φ = 253056.

The previous prime is 685859. The next prime is 685907. The reversal of 685880 is 88586.

It is a self number, because there is not a number n which added to its sum of digits gives 685880.

It is a congruent number.

It is an unprimeable number.

685880 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 140 + ... + 1179.

It is an arithmetic number, because the mean of its divisors is an integer number (51975).

2⁶⁸⁵⁸⁸⁰ is an apocalyptic number.

It is an amenable number.

685880 is an abundant number, since it is smaller than the sum of its proper divisors (977320).

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

685880 is a wasteful number, since it uses less digits than its factorization.

685880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1343 (or 1339 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 35.

The square root of 685880 is about 828.1787246724. The cubic root of 685880 is about 88.1893306579.

The spelling of 685880 in words is "six hundred eighty-five thousand, eight hundred eighty".