2161256561576 has 16 divisors (see below), whose sum is σ = 4631264060640. Its totient is φ = 926252812080.

The previous prime is 2161256561561. The next prime is 2161256561617. The reversal of 2161256561576 is 6751656521612.

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, 19296933530 + ... + 19296933641.

It is an arithmetic number, because the mean of its divisors is an integer number (289454003790).

Almost surely, 2^{2161256561576} is an apocalyptic number.

It is an amenable number.

2161256561576 is an abundant number, since it is smaller than the sum of its proper divisors (2470007499064).

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

2161256561576 is a wasteful number, since it uses less digits than its factorization.

2161256561576 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38593867184 (or 38593867180 counting only the distinct ones).

The product of its digits is 4536000, while the sum is 53.

The spelling of 2161256561576 in words is "two trillion, one hundred sixty-one billion, two hundred fifty-six million, five hundred sixty-one thousand, five hundred seventy-six".