666365043010665 has 16 divisors (see below), whose sum is σ = 1066184581622976. Its totient is φ = 355394518670400.

The previous prime is 666365043010651. The next prime is 666365043010739. The reversal of 666365043010665 is 566010340563666.

It is a happy number.

It is not a de Polignac number, because 666365043010665 - 2³⁹ = 665815287196777 is a prime.

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, 25494955 + ... + 44527775.

It is an arithmetic number, because the mean of its divisors is an integer number (66636536351436).

Almost surely, 2^{666365043010665} is an apocalyptic number.

It is an amenable number.

666365043010665 is a deficient number, since it is larger than the sum of its proper divisors (399819538612311).

666365043010665 is a wasteful number, since it uses less digits than its factorization.

666365043010665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21366920.

The product of its (nonzero) digits is 41990400, while the sum is 57.

The spelling of 666365043010665 in words is "six hundred sixty-six trillion, three hundred sixty-five billion, forty-three million, ten thousand, six hundred sixty-five".