686520 has 48 divisors (see below), whose sum is σ = 2232360. Its totient is φ = 182976.

The previous prime is 686519. The next prime is 686551. The reversal of 686520 is 25686.

686520 is a `hidden beast` number, since 6 + 8 + 652 + 0 = 666.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a nialpdrome in base 15.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 594 + ... + 1313.

2⁶⁸⁶⁵²⁰ is an apocalyptic number.

686520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

686520 is an abundant number, since it is smaller than the sum of its proper divisors (1545840).

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

686520 is a wasteful number, since it uses less digits than its factorization.

686520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1924 (or 1917 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 686520 is about 828.5650246058. The cubic root of 686520 is about 88.2167521823.

The spelling of 686520 in words is "six hundred eighty-six thousand, five hundred twenty".