686397678 has 16 divisors (see below), whose sum is σ = 1453548240. Its totient is φ = 215340416.

The previous prime is 686397653. The next prime is 686397689. The reversal of 686397678 is 876793686.

It is a super-2 number, since 2×686397678² = 942283544727583368, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3364593 + ... + 3364796.

It is an arithmetic number, because the mean of its divisors is an integer number (90846765).

Almost surely, 2^686397678 is an apocalyptic number.

686397678 is an abundant number, since it is smaller than the sum of its proper divisors (767150562).

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

686397678 is a wasteful number, since it uses less digits than its factorization.

686397678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6729411.

The product of its digits is 18289152, while the sum is 60.

The square root of 686397678 is about 26199.1923157948. The cubic root of 686397678 is about 882.1151247548.

The spelling of 686397678 in words is "six hundred eighty-six million, three hundred ninety-seven thousand, six hundred seventy-eight".