686516005768 has 8 divisors (see below), whose sum is σ = 1287217510830. Its totient is φ = 343258002880.

The previous prime is 686516005757. The next prime is 686516005789. The reversal of 686516005768 is 867500615686.

It can be written as a sum of positive squares in only one way, i.e., 665728710084 + 20787295684 = 815922^2 + 144178^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-4 number, since 4×686516005768⁴ (a number of 48 digits) contains 4444 as substring.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 42907250353 + ... + 42907250368.

Almost surely, 2^686516005768 is an apocalyptic number.

It is an amenable number.

686516005768 is a deficient number, since it is larger than the sum of its proper divisors (600701505062).

686516005768 is a wasteful number, since it uses less digits than its factorization.

686516005768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85814500727 (or 85814500723 counting only the distinct ones).

The product of its (nonzero) digits is 14515200, while the sum is 58.

The spelling of 686516005768 in words is "six hundred eighty-six billion, five hundred sixteen million, five thousand, seven hundred sixty-eight".