685870 has 16 divisors (see below), whose sum is σ = 1248048. Its totient is φ = 271360.

The previous prime is 685859. The next prime is 685907. The reversal of 685870 is 78586.

It is a congruent number.

It is an unprimeable number.

685870 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 7 ways as a sum of consecutive naturals, for example, 750 + ... + 1390.

It is an arithmetic number, because the mean of its divisors is an integer number (78003).

2⁶⁸⁵⁸⁷⁰ is an apocalyptic number.

685870 is a deficient number, since it is larger than the sum of its proper divisors (562178).

685870 is a wasteful number, since it uses less digits than its factorization.

685870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 755.

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 685870 is about 828.1726873062. The cubic root of 685870 is about 88.1889020612.

The spelling of 685870 in words is "six hundred eighty-five thousand, eight hundred seventy".