688668688 has 10 divisors (see below), whose sum is σ = 1334295614. Its totient is φ = 344334336.

The previous prime is 688668683. The next prime is 688668707. The reversal of 688668688 is 886866886.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 514745344 + 173923344 = 22688^2 + 13188^2 .

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 as a sum of consecutive naturals, namely, 21520881 + ... + 21520912.

Almost surely, 2^688668688 is an apocalyptic number.

It is an amenable number.

688668688 is a deficient number, since it is larger than the sum of its proper divisors (645626926).

688668688 is a wasteful number, since it uses less digits than its factorization.

688668688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43041801 (or 43041795 counting only the distinct ones).

The product of its digits is 42467328, while the sum is 64.

The square root of 688668688 is about 26242.4977469752. The cubic root of 688668688 is about 883.0869068701.

The spelling of 688668688 in words is "six hundred eighty-eight million, six hundred sixty-eight thousand, six hundred eighty-eight".