12256544026561 has 8 divisors (see below), whose sum is σ = 12989135413800. Its totient is φ = 11525243551488.

The previous prime is 12256544026549. The next prime is 12256544026619. The reversal of 12256544026561 is 16562044565221.

It can be written as a sum of positive squares in 4 ways, for example, as 2082638628225 + 10173905398336 = 1443135^2 + 3189656^2 .

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 12256544026561 - 2²⁹ = 12256007155649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12256544026261) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 322708486 + ... + 322746463.

It is an arithmetic number, because the mean of its divisors is an integer number (1623641926725).

Almost surely, 2^{12256544026561} is an apocalyptic number.

It is an amenable number.

12256544026561 is a deficient number, since it is larger than the sum of its proper divisors (732591387239).

12256544026561 is a wasteful number, since it uses less digits than its factorization.

12256544026561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 645456083.

The product of its (nonzero) digits is 3456000, while the sum is 49.

The spelling of 12256544026561 in words is "twelve trillion, two hundred fifty-six billion, five hundred forty-four million, twenty-six thousand, five hundred sixty-one".