668688886866 has 128 divisors (see below), whose sum is σ = 1844171513856. Its totient is φ = 155991847680.

The previous prime is 668688886847. The next prime is 668688886889.

668688886866 is nontrivially palindromic in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1282330 + ... + 1726773.

It is an arithmetic number, because the mean of its divisors is an integer number (14407589952).

Almost surely, 2^668688886866 is an apocalyptic number.

668688886866 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

668688886866 is an abundant number, since it is smaller than the sum of its proper divisors (1175482626990).

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

668688886866 is a wasteful number, since it uses less digits than its factorization.

668688886866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3009176.

The product of its digits is 12230590464, while the sum is 84.

The spelling of 668688886866 in words is "six hundred sixty-eight billion, six hundred eighty-eight million, eight hundred eighty-six thousand, eight hundred sixty-six".