686438566 has 24 divisors (see below), whose sum is σ = 1133511120. Its totient is φ = 311538480.

The previous prime is 686438531. The next prime is 686438587. The reversal of 686438566 is 665834686.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 191095 + ... + 194653.

It is an arithmetic number, because the mean of its divisors is an integer number (47229630).

Almost surely, 2^686438566 is an apocalyptic number.

686438566 is a deficient number, since it is larger than the sum of its proper divisors (447072554).

686438566 is a wasteful number, since it uses less digits than its factorization.

686438566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4380 (or 4369 counting only the distinct ones).

The product of its digits is 4976640, while the sum is 52.

The square root of 686438566 is about 26199.9726335735. The cubic root of 686438566 is about 882.1326399690.

The spelling of 686438566 in words is "six hundred eighty-six million, four hundred thirty-eight thousand, five hundred sixty-six".