666702207666 has 32 divisors (see below), whose sum is σ = 1616247777600. Its totient is φ = 202030971840.

The previous prime is 666702207641. The next prime is 666702207679.

666702207666 is nontrivially palindromic in base 10.

666702207666 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 561196551 + ... + 561197738.

It is an arithmetic number, because the mean of its divisors is an integer number (50507743050).

Almost surely, 2^666702207666 is an apocalyptic number.

666702207666 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

666702207666 is an abundant number, since it is smaller than the sum of its proper divisors (949545569934).

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

666702207666 is a wasteful number, since it uses less digits than its factorization.

666702207666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1122394311 (or 1122394305 counting only the distinct ones).

The product of its (nonzero) digits is 9144576, while the sum is 54.

The spelling of 666702207666 in words is "six hundred sixty-six billion, seven hundred two million, two hundred seven thousand, six hundred sixty-six".