668788 has 6 divisors (see below), whose sum is σ = 1170386. Its totient is φ = 334392.

The previous prime is 668761. The next prime is 668791. The reversal of 668788 is 887866.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 605284 + 63504 = 778^2 + 252^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83595 + ... + 83602.

2⁶⁶⁸⁷⁸⁸ is an apocalyptic number.

It is an amenable number.

668788 is a deficient number, since it is larger than the sum of its proper divisors (501598).

668788 is a wasteful number, since it uses less digits than its factorization.

668788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167201 (or 167199 counting only the distinct ones).

The product of its digits is 129024, while the sum is 43.

The square root of 668788 is about 817.7945952377. The cubic root of 668788 is about 87.4506061360.

The spelling of 668788 in words is "six hundred sixty-eight thousand, seven hundred eighty-eight".