12666533656 has 16 divisors (see below), whose sum is σ = 27142572240. Its totient is φ = 5428514400.

The previous prime is 12666533641. The next prime is 12666533681. The reversal of 12666533656 is 65633566621.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113093995 + ... + 113094106.

It is an arithmetic number, because the mean of its divisors is an integer number (1696410765).

Almost surely, 2^12666533656 is an apocalyptic number.

It is an amenable number.

12666533656 is an abundant number, since it is smaller than the sum of its proper divisors (14476038584).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12666533656 is a wasteful number, since it uses less digits than its factorization.

12666533656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226188114 (or 226188110 counting only the distinct ones).

The product of its digits is 3499200, while the sum is 49.

The spelling of 12666533656 in words is "twelve billion, six hundred sixty-six million, five hundred thirty-three thousand, six hundred fifty-six".