165959 has 4 divisors (see below), whose sum is σ = 168504. Its totient is φ = 163416.

The previous prime is 165947. The next prime is 165961. The reversal of 165959 is 959561.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 165959 - 2⁸ = 165703 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 (165059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1172 + ... + 1305.

It is an arithmetic number, because the mean of its divisors is an integer number (42126).

2¹⁶⁵⁹⁵⁹ is an apocalyptic number.

165959 is a deficient number, since it is larger than the sum of its proper divisors (2545).

165959 is an equidigital number, since it uses as much as digits as its factorization.

165959 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2544.

The product of its digits is 12150, while the sum is 35.

The square root of 165959 is about 407.3806573710. The cubic root of 165959 is about 54.9541215205.

The spelling of 165959 in words is "one hundred sixty-five thousand, nine hundred fifty-nine".