165665511161 has 4 divisors (see below), whose sum is σ = 165714369024. Its totient is φ = 165616653300.

The previous prime is 165665511149. The next prime is 165665511181. The reversal of 165665511161 is 161115566561.

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 165665511161 - 2¹⁰ = 165665510137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165665511101) 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, 24423845 + ... + 24430626.

It is an arithmetic number, because the mean of its divisors is an integer number (41428592256).

Almost surely, 2^165665511161 is an apocalyptic number.

It is an amenable number.

165665511161 is a deficient number, since it is larger than the sum of its proper divisors (48857863).

165665511161 is an equidigital number, since it uses as much as digits as its factorization.

165665511161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48857862.

The product of its digits is 162000, while the sum is 44.

The spelling of 165665511161 in words is "one hundred sixty-five billion, six hundred sixty-five million, five hundred eleven thousand, one hundred sixty-one".