686808625217 has 16 divisors (see below), whose sum is σ = 806995875840. Its totient is φ = 576260179200.

The previous prime is 686808625213. The next prime is 686808625241. The reversal of 686808625217 is 712526808686.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 686808625217 - 2² = 686808625213 is a prime.

It is not an unprimeable number, because it can be changed into a prime (686808625211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 665417 + ... + 1347737.

It is an arithmetic number, because the mean of its divisors is an integer number (50437242240).

Almost surely, 2^686808625217 is an apocalyptic number.

It is an amenable number.

686808625217 is a deficient number, since it is larger than the sum of its proper divisors (120187250623).

686808625217 is a wasteful number, since it uses less digits than its factorization.

686808625217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 689384.

The product of its (nonzero) digits is 15482880, while the sum is 59.

The spelling of 686808625217 in words is "six hundred eighty-six billion, eight hundred eight million, six hundred twenty-five thousand, two hundred seventeen".