688680 has 48 divisors (see below), whose sum is σ = 2239380. Its totient is φ = 183552.

The previous prime is 688679. The next prime is 688697. The reversal of 688680 is 86886.

It can be written as a sum of positive squares in 2 ways, for example, as 675684 + 12996 = 822^2 + 114^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 597 + ... + 1316.

2⁶⁸⁸⁶⁸⁰ is an apocalyptic number.

688680 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

688680 is an abundant number, since it is smaller than the sum of its proper divisors (1550700).

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

688680 is a wasteful number, since it uses less digits than its factorization.

688680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1930 (or 1923 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 688680 is about 829.8674592970. The cubic root of 688680 is about 88.3091742008.

The spelling of 688680 in words is "six hundred eighty-eight thousand, six hundred eighty".