668628826866 has 96 divisors (see below), whose sum is σ = 1945102094208. Its totient is φ = 160310603520.

The previous prime is 668628826861. The next prime is 668628826867.

668628826866 is a `hidden beast` number, since 6 + 6 + 86 + 288 + 268 + 6 + 6 = 666.

668628826866 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 668628826794 and 668628826803.

It is not an unprimeable number, because it can be changed into a prime (668628826861) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 18536451 + ... + 18572486.

It is an arithmetic number, because the mean of its divisors is an integer number (20261480148).

Almost surely, 2^668628826866 is an apocalyptic number.

668628826866 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

668628826866 is an abundant number, since it is smaller than the sum of its proper divisors (1276473267342).

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

668628826866 is a wasteful number, since it uses less digits than its factorization.

668628826866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37108976 (or 37108973 counting only the distinct ones).

The product of its digits is 764411904, while the sum is 72.

The spelling of 668628826866 in words is "six hundred sixty-eight billion, six hundred twenty-eight million, eight hundred twenty-six thousand, eight hundred sixty-six".