165571161 has 32 divisors (see below), whose sum is σ = 261101568. Its totient is φ = 91359360.

The previous prime is 165571151. The next prime is 165571183. The reversal of 165571161 is 161175561.

It is not a de Polignac number, because 165571161 - 2¹⁸ = 165309017 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (165571151) 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, 87750 + ... + 89616.

It is an arithmetic number, because the mean of its divisors is an integer number (8159424).

Almost surely, 2^165571161 is an apocalyptic number.

It is an amenable number.

165571161 is a deficient number, since it is larger than the sum of its proper divisors (95530407).

165571161 is a wasteful number, since it uses less digits than its factorization.

165571161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2021.

The product of its digits is 6300, while the sum is 33.

The square root of 165571161 is about 12867.4457838376. The cubic root of 165571161 is about 549.1127966216.

The spelling of 165571161 in words is "one hundred sixty-five million, five hundred seventy-one thousand, one hundred sixty-one".