688181768 has 8 divisors (see below), whose sum is σ = 1290340830. Its totient is φ = 344090880.

The previous prime is 688181713. The next prime is 688181773. The reversal of 688181768 is 867181886.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 672987364 + 15194404 = 25942^2 + 3898^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43011353 + ... + 43011368.

Almost surely, 2^688181768 is an apocalyptic number.

It is an amenable number.

688181768 is a deficient number, since it is larger than the sum of its proper divisors (602159062).

688181768 is a wasteful number, since it uses less digits than its factorization.

688181768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86022727 (or 86022723 counting only the distinct ones).

The product of its digits is 1032192, while the sum is 53.

The square root of 688181768 is about 26233.2187883988. The cubic root of 688181768 is about 882.8787302992.

The spelling of 688181768 in words is "six hundred eighty-eight million, one hundred eighty-one thousand, seven hundred sixty-eight".