685878 has 16 divisors (see below), whose sum is σ = 1390080. Its totient is φ = 225576.

The previous prime is 685859. The next prime is 685907. The reversal of 685878 is 878586.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 250 + ... + 1197.

It is an arithmetic number, because the mean of its divisors is an integer number (86880).

2⁶⁸⁵⁸⁷⁸ is an apocalyptic number.

685878 is an abundant number, since it is smaller than the sum of its proper divisors (704202).

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

685878 is a wasteful number, since it uses less digits than its factorization.

685878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1531.

The product of its digits is 107520, while the sum is 42.

The square root of 685878 is about 828.1775172027. The cubic root of 685878 is about 88.1892449389.

The spelling of 685878 in words is "six hundred eighty-five thousand, eight hundred seventy-eight".