686808321 has 16 divisors (see below), whose sum is σ = 951091200. Its totient is φ = 440529488.

The previous prime is 686808299. The next prime is 686808323. The reversal of 686808321 is 123808686.

It is a cyclic number.

It is not a de Polignac number, because 686808321 - 2⁵ = 686808289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (686808323) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32961 + ... + 49598.

It is an arithmetic number, because the mean of its divisors is an integer number (59443200).

Almost surely, 2^686808321 is an apocalyptic number.

It is an amenable number.

686808321 is a deficient number, since it is larger than the sum of its proper divisors (264282879).

686808321 is a wasteful number, since it uses less digits than its factorization.

686808321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82668.

The product of its (nonzero) digits is 110592, while the sum is 42.

The square root of 686808321 is about 26207.0280840846. The cubic root of 686808321 is about 882.2910005384.

The spelling of 686808321 in words is "six hundred eighty-six million, eight hundred eight thousand, three hundred twenty-one".