12956561819691 has 16 divisors (see below), whose sum is σ = 19869086010624. Its totient is φ = 7356591968544.

The previous prime is 12956561819689. The next prime is 12956561819701. The reversal of 12956561819691 is 19691816565921.

12956561819691 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12956561819691 - 2¹ = 12956561819689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12956561819191) 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, 1964898405 + ... + 1964904998.

It is an arithmetic number, because the mean of its divisors is an integer number (1241817875664).

Almost surely, 2^{12956561819691} is an apocalyptic number.

12956561819691 is a deficient number, since it is larger than the sum of its proper divisors (6912524190933).

12956561819691 is a wasteful number, since it uses less digits than its factorization.

12956561819691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3929803570.

The product of its digits is 62985600, while the sum is 69.

The spelling of 12956561819691 in words is "twelve trillion, nine hundred fifty-six billion, five hundred sixty-one million, eight hundred nineteen thousand, six hundred ninety-one".