686215494 has 24 divisors (see below), whose sum is σ = 1489249632. Its totient is φ = 228361680.

The previous prime is 686215471. The next prime is 686215501. The reversal of 686215494 is 494512686.

686215494 is a `hidden beast` number, since 6 + 86 + 21 + 549 + 4 = 666.

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, 20062 + ... + 42129.

It is an arithmetic number, because the mean of its divisors is an integer number (62052068).

Almost surely, 2^686215494 is an apocalyptic number.

686215494 is an abundant number, since it is smaller than the sum of its proper divisors (803034138).

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

686215494 is a wasteful number, since it uses less digits than its factorization.

686215494 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62812 (or 62809 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The square root of 686215494 is about 26195.7151839762. The cubic root of 686215494 is about 882.0370740428.

The spelling of 686215494 in words is "six hundred eighty-six million, two hundred fifteen thousand, four hundred ninety-four".