686506880 has 128 divisors (see below), whose sum is σ = 1720478880. Its totient is φ = 261660672.

The previous prime is 686506867. The next prime is 686506889. The reversal of 686506880 is 88605686.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686506889) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1254767 + ... + 1255313.

Almost surely, 2^686506880 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 686506880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (860239440).

686506880 is an abundant number, since it is smaller than the sum of its proper divisors (1033972000).

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

686506880 is a wasteful number, since it uses less digits than its factorization.

686506880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 656 (or 644 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 47.

The square root of 686506880 is about 26201.2763047910. The cubic root of 686506880 is about 882.1619021216.

The spelling of 686506880 in words is "six hundred eighty-six million, five hundred six thousand, eight hundred eighty".