666206705943 has 12 divisors (see below), whose sum is σ = 963252303520. Its totient is φ = 443697621696.

The previous prime is 666206705917. The next prime is 666206705947. The reversal of 666206705943 is 349507602666.

It is not a de Polignac number, because 666206705943 - 2⁹ = 666206705431 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 666206705943.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666206705947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36672271 + ... + 36690432.

Almost surely, 2^666206705943 is an apocalyptic number.

666206705943 is a deficient number, since it is larger than the sum of its proper divisors (297045597577).

666206705943 is a wasteful number, since it uses less digits than its factorization.

666206705943 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73363718 (or 73363715 counting only the distinct ones).

The product of its (nonzero) digits is 9797760, while the sum is 54.

The spelling of 666206705943 in words is "six hundred sixty-six billion, two hundred six million, seven hundred five thousand, nine hundred forty-three".