12536663521 has 16 divisors (see below), whose sum is σ = 13450526208. Its totient is φ = 11655705600.

The previous prime is 12536663507. The next prime is 12536663539.

12536663521 is nontrivially palindromic in base 10.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12536663521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12536663551) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 231025 + ... + 280081.

It is an arithmetic number, because the mean of its divisors is an integer number (840657888).

Almost surely, 2^12536663521 is an apocalyptic number.

It is an amenable number.

12536663521 is a deficient number, since it is larger than the sum of its proper divisors (913862687).

12536663521 is a wasteful number, since it uses less digits than its factorization.

12536663521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49392.

The product of its digits is 194400, while the sum is 40.

The spelling of 12536663521 in words is "twelve billion, five hundred thirty-six million, six hundred sixty-three thousand, five hundred twenty-one".