686959656 has 64 divisors (see below), whose sum is σ = 1806840000. Its totient is φ = 217330176.

The previous prime is 686959631. The next prime is 686959667. The reversal of 686959656 is 656959686.

It is a self number, because there is not a number n which added to its sum of digits gives 686959656.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32700 + ... + 49428.

It is an arithmetic number, because the mean of its divisors is an integer number (28231875).

Almost surely, 2^686959656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686959656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (903420000).

686959656 is an abundant number, since it is smaller than the sum of its proper divisors (1119880344).

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

686959656 is a wasteful number, since it uses less digits than its factorization.

686959656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16826 (or 16822 counting only the distinct ones).

The product of its digits is 20995200, while the sum is 60.

The square root of 686959656 is about 26209.9152230601. The cubic root of 686959656 is about 882.3557986773.

The spelling of 686959656 in words is "six hundred eighty-six million, nine hundred fifty-nine thousand, six hundred fifty-six".