165571 has 12 divisors (see below), whose sum is σ = 200640. Its totient is φ = 136080.

The previous prime is 165569. The next prime is 165587. The reversal of 165571 is 175561.

It is not a de Polignac number, because 165571 - 2¹ = 165569 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165511) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1465 + ... + 1573.

It is an arithmetic number, because the mean of its divisors is an integer number (16720).

2¹⁶⁵⁵⁷¹ is an apocalyptic number.

165571 is a deficient number, since it is larger than the sum of its proper divisors (35069).

165571 is a wasteful number, since it uses less digits than its factorization.

165571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154 (or 147 counting only the distinct ones).

The product of its digits is 1050, while the sum is 25.

The square root of 165571 is about 406.9041656213. The cubic root of 165571 is about 54.9112618637.

The spelling of 165571 in words is "one hundred sixty-five thousand, five hundred seventy-one".