668658383856866 has 8 divisors (see below), whose sum is σ = 1080140466230364. Its totient is φ = 308611561780080.

The previous prime is 668658383856787. The next prime is 668658383856889.

668658383856866 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 2 ways, for example, as 656575077885841 + 12083305971025 = 25623721^2 + 3476105^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12858815074145 + ... + 12858815074196.

Almost surely, 2^{668658383856866} is an apocalyptic number.

668658383856866 is a deficient number, since it is larger than the sum of its proper divisors (411482082373498).

668658383856866 is a wasteful number, since it uses less digits than its factorization.

668658383856866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25717630148356.

The product of its digits is 343985356800, while the sum is 92.

The spelling of 668658383856866 in words is "six hundred sixty-eight trillion, six hundred fifty-eight billion, three hundred eighty-three million, eight hundred fifty-six thousand, eight hundred sixty-six".