15566056161 has 4 divisors (see below), whose sum is σ = 20754741552. Its totient is φ = 10377370772.

The previous prime is 15566056157. The next prime is 15566056249. The reversal of 15566056161 is 16165066551.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 15566056161 - 2² = 15566056157 is a prime.

It is not an unprimeable number, because it can be changed into a prime (15566056141) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2594342691 + ... + 2594342696.

It is an arithmetic number, because the mean of its divisors is an integer number (5188685388).

Almost surely, 2^15566056161 is an apocalyptic number.

It is an amenable number.

15566056161 is a deficient number, since it is larger than the sum of its proper divisors (5188685391).

15566056161 is an equidigital number, since it uses as much as digits as its factorization.

15566056161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5188685390.

The product of its (nonzero) digits is 162000, while the sum is 42.

The spelling of 15566056161 in words is "fifteen billion, five hundred sixty-six million, fifty-six thousand, one hundred sixty-one".