686205502686 has 64 divisors (see below), whose sum is σ = 1663712559360. Its totient is φ = 207918053280.

The previous prime is 686205502607. The next prime is 686205502699.

686205502686 is a `hidden beast` number, since 6 + 8 + 6 + 2 + 0 + 550 + 2 + 6 + 86 = 666.

686205502686 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5754460 + ... + 5872496.

It is an arithmetic number, because the mean of its divisors is an integer number (25995508740).

Almost surely, 2^686205502686 is an apocalyptic number.

686205502686 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

686205502686 is an abundant number, since it is smaller than the sum of its proper divisors (977507056674).

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

686205502686 is a wasteful number, since it uses less digits than its factorization.

686205502686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127846 (or 127840 counting only the distinct ones).

The product of its (nonzero) digits is 8294400, while the sum is 54.

The spelling of 686205502686 in words is "six hundred eighty-six billion, two hundred five million, five hundred two thousand, six hundred eighty-six".