686695 has 4 divisors (see below), whose sum is σ = 824040. Its totient is φ = 549352.

The previous prime is 686687. The next prime is 686723. The reversal of 686695 is 596686.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 596686 = 2 ⋅298343.

It is a cyclic number.

It is not a de Polignac number, because 686695 - 2³ = 686687 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68665 + ... + 68674.

It is an arithmetic number, because the mean of its divisors is an integer number (206010).

2⁶⁸⁶⁶⁹⁵ is an apocalyptic number.

686695 is a deficient number, since it is larger than the sum of its proper divisors (137345).

686695 is a wasteful number, since it uses less digits than its factorization.

686695 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137344.

The product of its digits is 77760, while the sum is 40.

The square root of 686695 is about 828.6706221413. The cubic root of 686695 is about 88.2242472880.

Subtracting from 686695 its reverse (596686), we obtain a palindrome (90009).

The spelling of 686695 in words is "six hundred eighty-six thousand, six hundred ninety-five".