688668680 has 64 divisors (see below), whose sum is σ = 1864080000. Its totient is φ = 223686144.

The previous prime is 688668671. The next prime is 688668683. The reversal of 688668680 is 86866886.

It is a Harshad number since it is a multiple of its sum of digits (56).

It is not an unprimeable number, because it can be changed into a prime (688668683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59405 + ... + 70044.

It is an arithmetic number, because the mean of its divisors is an integer number (29126250).

Almost surely, 2^688668680 is an apocalyptic number.

It is an amenable number.

688668680 is an abundant number, since it is smaller than the sum of its proper divisors (1175411320).

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

688668680 is a wasteful number, since it uses less digits than its factorization.

688668680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129486 (or 129482 counting only the distinct ones).

The product of its (nonzero) digits is 5308416, while the sum is 56.

The square root of 688668680 is about 26242.4975945507. The cubic root of 688668680 is about 883.0869034506.

The spelling of 688668680 in words is "six hundred eighty-eight million, six hundred sixty-eight thousand, six hundred eighty".