165939 has 4 divisors (see below), whose sum is σ = 221256. Its totient is φ = 110624.

The previous prime is 165931. The next prime is 165941. The reversal of 165939 is 939561.

165939 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

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 165939 - 2³ = 165931 is a prime.

It is a D-number.

165939 is strictly pandigital in base 7.

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (165931) 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, 27654 + ... + 27659.

It is an arithmetic number, because the mean of its divisors is an integer number (55314).

2¹⁶⁵⁹³⁹ is an apocalyptic number.

165939 is a deficient number, since it is larger than the sum of its proper divisors (55317).

165939 is an equidigital number, since it uses as much as digits as its factorization.

165939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55316.

The product of its digits is 7290, while the sum is 33.

The square root of 165939 is about 407.3561095651. The cubic root of 165939 is about 54.9519138938.

The spelling of 165939 in words is "one hundred sixty-five thousand, nine hundred thirty-nine".