688880680 has 16 divisors (see below), whose sum is σ = 1549981620. Its totient is φ = 275552256.

The previous prime is 688880671. The next prime is 688880719. The reversal of 688880680 is 86088886.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 684240964 + 4639716 = 26158^2 + 2154^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8610969 + ... + 8611048.

Almost surely, 2^688880680 is an apocalyptic number.

It is an amenable number.

688880680 is an abundant number, since it is smaller than the sum of its proper divisors (861100940).

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

688880680 is a wasteful number, since it uses less digits than its factorization.

688880680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17222028 (or 17222024 counting only the distinct ones).

The product of its (nonzero) digits is 1179648, while the sum is 52.

The square root of 688880680 is about 26246.5365334171. The cubic root of 688880680 is about 883.1775107443.

It can be divided in two parts, 6888806 and 80, that added together give a palindrome (6888886).

The spelling of 688880680 in words is "six hundred eighty-eight million, eight hundred eighty thousand, six hundred eighty".