12666275665 has 4 divisors (see below), whose sum is σ = 15199530804. Its totient is φ = 10133020528.

The previous prime is 12666275639. The next prime is 12666275681. The reversal of 12666275665 is 56657266621.

12666275665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1385923984 + 11280351681 = 37228^2 + 106209^2 .

It is a cyclic number.

It is not a de Polignac number, because 12666275665 - 2¹⁹ = 12665751377 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1266627562 + ... + 1266627571.

It is an arithmetic number, because the mean of its divisors is an integer number (3799882701).

Almost surely, 2^12666275665 is an apocalyptic number.

It is an amenable number.

12666275665 is a deficient number, since it is larger than the sum of its proper divisors (2533255139).

12666275665 is an equidigital number, since it uses as much as digits as its factorization.

12666275665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2533255138.

The product of its digits is 5443200, while the sum is 52.

The spelling of 12666275665 in words is "twelve billion, six hundred sixty-six million, two hundred seventy-five thousand, six hundred sixty-five".