12561331334636 has 12 divisors (see below), whose sum is σ = 25122662669328. Its totient is φ = 5383427714832.

The previous prime is 12561331334581. The next prime is 12561331334687. The reversal of 12561331334636 is 63643313316521.

12561331334636 is an admirable 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, 224309488091 + ... + 224309488146.

It is an arithmetic number, because the mean of its divisors is an integer number (2093555222444).

Almost surely, 2^{12561331334636} is an apocalyptic number.

It is an amenable number.

12561331334636 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

12561331334636 is a wasteful number, since it uses less digits than its factorization.

12561331334636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 448618976248 (or 448618976246 counting only the distinct ones).

The product of its digits is 2099520, while the sum is 47.

The spelling of 12561331334636 in words is "twelve trillion, five hundred sixty-one billion, three hundred thirty-one million, three hundred thirty-four thousand, six hundred thirty-six".