165565747565561 has 32 divisors (see below), whose sum is σ = 195401089843200. Its totient is φ = 137279907172800.

The previous prime is 165565747565539. The next prime is 165565747565671.

165565747565561 is nontrivially palindromic in base 10.

165565747565561 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 165565747565561 - 2³⁴ = 165548567696377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165565747565161) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8026641530 + ... + 8026662156.

It is an arithmetic number, because the mean of its divisors is an integer number (6106284057600).

Almost surely, 2^{165565747565561} is an apocalyptic number.

It is an amenable number.

165565747565561 is a deficient number, since it is larger than the sum of its proper divisors (29835342277639).

165565747565561 is a wasteful number, since it uses less digits than its factorization.

165565747565561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33885.

The product of its digits is 3969000000, while the sum is 74.

The spelling of 165565747565561 in words is "one hundred sixty-five trillion, five hundred sixty-five billion, seven hundred forty-seven million, five hundred sixty-five thousand, five hundred sixty-one".