686306656 has 24 divisors (see below), whose sum is σ = 1544190480. Its totient is φ = 294131328.

The previous prime is 686306651. The next prime is 686306659. The reversal of 686306656 is 656603686.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686306651) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1531711 + ... + 1532158.

It is an arithmetic number, because the mean of its divisors is an integer number (64341270).

Almost surely, 2^686306656 is an apocalyptic number.

It is an amenable number.

686306656 is an abundant number, since it is smaller than the sum of its proper divisors (857883824).

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

686306656 is a wasteful number, since it uses less digits than its factorization.

686306656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3063886 (or 3063878 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 46.

The square root of 686306656 is about 26197.4551435822. The cubic root of 686306656 is about 882.0761311146.

It can be divided in two parts, 686 and 306656, that multiplied together give a square (210366016 = 14504²).

The spelling of 686306656 in words is "six hundred eighty-six million, three hundred six thousand, six hundred fifty-six".