165945 has 32 divisors (see below), whose sum is σ = 306432. Its totient is φ = 76032.

The previous prime is 165941. The next prime is 165947. The reversal of 165945 is 549561.

165945 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 165945 - 2² = 165941 is a prime.

165945 is strictly pandigital in base 7.

It is not an unprimeable number, because it can be changed into a prime (165941) 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 31 ways as a sum of consecutive naturals, for example, 4467 + ... + 4503.

It is an arithmetic number, because the mean of its divisors is an integer number (9576).

2¹⁶⁵⁹⁴⁵ is an apocalyptic number.

165945 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

165945 is a deficient number, since it is larger than the sum of its proper divisors (140487).

165945 is a wasteful number, since it uses less digits than its factorization.

165945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81.

The product of its digits is 5400, while the sum is 30.

The square root of 165945 is about 407.3634740622. The cubic root of 165945 is about 54.9525762004.

The spelling of 165945 in words is "one hundred sixty-five thousand, nine hundred forty-five".