686875 has 20 divisors (see below), whose sum is σ = 987184. Its totient is φ = 468000.

The previous prime is 686863. The next prime is 686879. The reversal of 686875 is 578686.

It is not a de Polignac number, because 686875 - 2⁵ = 686843 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (686879) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 4297 + ... + 4453.

2⁶⁸⁶⁸⁷⁵ is an apocalyptic number.

686875 is a deficient number, since it is larger than the sum of its proper divisors (300309).

686875 is an equidigital number, since it uses as much as digits as its factorization.

686875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184 (or 169 counting only the distinct ones).

The product of its digits is 80640, while the sum is 40.

The square root of 686875 is about 828.7792227125. The cubic root of 686875 is about 88.2319552113.

The spelling of 686875 in words is "six hundred eighty-six thousand, eight hundred seventy-five".