668828866 has 4 divisors (see below), whose sum is σ = 1003243302. Its totient is φ = 334414432.

The previous prime is 668828843. The next prime is 668828869.

It is a happy number.

668828866 is nontrivially palindromic in base 10.

668828866 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 334707025 + 334121841 = 18295^2 + 18279^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 668828866.

It is not an unprimeable number, because it can be changed into a prime (668828869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 167207215 + ... + 167207218.

Almost surely, 2^668828866 is an apocalyptic number.

668828866 is a deficient number, since it is larger than the sum of its proper divisors (334414436).

668828866 is a wasteful number, since it uses less digits than its factorization.

668828866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334414435.

The product of its digits is 10616832, while the sum is 58.

The square root of 668828866 is about 25861.7258898164. The cubic root of 668828866 is about 874.5238731010.

The spelling of 668828866 in words is "six hundred sixty-eight million, eight hundred twenty-eight thousand, eight hundred sixty-six".