666791305361 has 4 divisors (see below), whose sum is σ = 666794174832. Its totient is φ = 666788435892.

The previous prime is 666791305331. The next prime is 666791305381. The reversal of 666791305361 is 163503197666.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 666791305361 - 2²⁶ = 666724196497 is a prime.

It is a super-2 number, since 2×666791305361² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666791305321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1052171 + ... + 1562256.

It is an arithmetic number, because the mean of its divisors is an integer number (166698543708).

Almost surely, 2^666791305361 is an apocalyptic number.

It is an amenable number.

666791305361 is a deficient number, since it is larger than the sum of its proper divisors (2869471).

666791305361 is a wasteful number, since it uses less digits than its factorization.

666791305361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2869470.

The product of its (nonzero) digits is 3674160, while the sum is 53.

The spelling of 666791305361 in words is "six hundred sixty-six billion, seven hundred ninety-one million, three hundred five thousand, three hundred sixty-one".