12665551121 has 8 divisors (see below), whose sum is σ = 13022354688. Its totient is φ = 12311028000.

The previous prime is 12665551111. The next prime is 12665551127. The reversal of 12665551121 is 12115556621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12665551121 - 2²² = 12661356817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12665551127) 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 7 ways as a sum of consecutive naturals, for example, 558845 + ... + 581066.

It is an arithmetic number, because the mean of its divisors is an integer number (1627794336).

Almost surely, 2^12665551121 is an apocalyptic number.

It is an amenable number.

12665551121 is a deficient number, since it is larger than the sum of its proper divisors (356803567).

12665551121 is a wasteful number, since it uses less digits than its factorization.

12665551121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1140223.

The product of its digits is 18000, while the sum is 35.

The spelling of 12665551121 in words is "twelve billion, six hundred sixty-five million, five hundred fifty-one thousand, one hundred twenty-one".