686605056 has 72 divisors (see below), whose sum is σ = 1831334064. Its totient is φ = 228372480.

The previous prime is 686605043. The next prime is 686605057. The reversal of 686605056 is 650506686.

It is a junction number, because it is equal to n+sod(n) for n = 686604999 and 686605017.

It is not an unprimeable number, because it can be changed into a prime (686605057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 580786 + ... + 581966.

Almost surely, 2^686605056 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 686605056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (915667032).

686605056 is an abundant number, since it is smaller than the sum of its proper divisors (1144729008).

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

686605056 is a wasteful number, since it uses less digits than its factorization.

686605056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1957 (or 1943 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 42.

The square root of 686605056 is about 26203.1497343354. The cubic root of 686605056 is about 882.2039521972.

The spelling of 686605056 in words is "six hundred eighty-six million, six hundred five thousand, fifty-six".