165951 has 6 divisors (see below), whose sum is σ = 239720. Its totient is φ = 110628.

The previous prime is 165947. The next prime is 165961. The reversal of 165951 is 159561.

165951 is a `hidden beast` number, since 1 + 659 + 5 + 1 = 666.

165951 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 165951 - 2² = 165947 is a prime.

It is a Duffinian number.

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165901) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9211 + ... + 9228.

2¹⁶⁵⁹⁵¹ is an apocalyptic number.

165951 is a deficient number, since it is larger than the sum of its proper divisors (73769).

165951 is a wasteful number, since it uses less digits than its factorization.

165951 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18445 (or 18442 counting only the distinct ones).

The product of its digits is 1350, while the sum is 27.

The square root of 165951 is about 407.3708384261. The cubic root of 165951 is about 54.9532384911.

The spelling of 165951 in words is "one hundred sixty-five thousand, nine hundred fifty-one".