12817860257561 has 8 divisors (see below), whose sum is σ = 12859497268800. Its totient is φ = 12776225952240.

The previous prime is 12817860257551. The next prime is 12817860257599. The reversal of 12817860257561 is 16575206871821.

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 12817860257561 - 2³⁸ = 12542982350617 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12817860257561.

It is not an unprimeable number, because it can be changed into a prime (12817860257551) 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, 9039050 + ... + 10360508.

It is an arithmetic number, because the mean of its divisors is an integer number (1607437158600).

Almost surely, 2^{12817860257561} is an apocalyptic number.

It is an amenable number.

12817860257561 is a deficient number, since it is larger than the sum of its proper divisors (41637011239).

12817860257561 is a wasteful number, since it uses less digits than its factorization.

12817860257561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1352959.

The product of its (nonzero) digits is 11289600, while the sum is 59.

The spelling of 12817860257561 in words is "twelve trillion, eight hundred seventeen billion, eight hundred sixty million, two hundred fifty-seven thousand, five hundred sixty-one".