686542865 has 32 divisors (see below), whose sum is σ = 891648000. Its totient is φ = 505821888.

The previous prime is 686542849. The next prime is 686542891. The reversal of 686542865 is 568245686.

It is a cyclic number.

It is not a de Polignac number, because 686542865 - 2⁴ = 686542849 is a prime.

It is a super-2 number, since 2×686542865² = 942682210964816450, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 798806 + ... + 799664.

It is an arithmetic number, because the mean of its divisors is an integer number (27864000).

Almost surely, 2^686542865 is an apocalyptic number.

It is an amenable number.

686542865 is a deficient number, since it is larger than the sum of its proper divisors (205105135).

686542865 is a wasteful number, since it uses less digits than its factorization.

686542865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1109.

The product of its digits is 2764800, while the sum is 50.

The square root of 686542865 is about 26201.9629989816. The cubic root of 686542865 is about 882.1773154371.

The spelling of 686542865 in words is "six hundred eighty-six million, five hundred forty-two thousand, eight hundred sixty-five".