It is a sphenic number, since it is the product of 3 distinct primes.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-666261662030017 is a prime.
It is a Duffinian number.
Almost surely, 2666261662030017 is an apocalyptic number.
It is an amenable number.
666261662030017 is a wasteful number, since it uses less digits than its factorization.
666261662030017 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 9839943.
The spelling of 666261662030017 in words is "six hundred sixty-six trillion, two hundred sixty-one billion, six hundred sixty-two million, thirty thousand, seventeen".