685188 has 36 divisors (see below), whose sum is σ = 1980160. Its totient is φ = 195696.

The previous prime is 685177. The next prime is 685199. The reversal of 685188 is 881586.

It is an interprime number because it is at equal distance from previous prime (685177) and next prime (685199).

It is a tau number, because it is divible by the number of its divisors (36).

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1108 + ... + 1611.

2⁶⁸⁵¹⁸⁸ is an apocalyptic number.

It is an amenable number.

685188 is an abundant number, since it is smaller than the sum of its proper divisors (1294972).

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

685188 is a wasteful number, since it uses less digits than its factorization.

685188 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2736 (or 2731 counting only the distinct ones).

The product of its digits is 15360, while the sum is 36.

The square root of 685188 is about 827.7608350242. The cubic root of 685188 is about 88.1596619344.

The spelling of 685188 in words is "six hundred eighty-five thousand, one hundred eighty-eight".