168591 has 4 divisors (see below), whose sum is σ = 224792. Its totient is φ = 112392.

The previous prime is 168559. The next prime is 168599. The reversal of 168591 is 195861.

It is a happy number.

168591 is digitally balanced in base 2, 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, and also an emirpimes, since its reverse is a distinct semiprime: 195861 = 3 ⋅65287.

It is not a de Polignac number, because 168591 - 2⁵ = 168559 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (168599) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28096 + ... + 28101.

It is an arithmetic number, because the mean of its divisors is an integer number (56198).

2¹⁶⁸⁵⁹¹ is an apocalyptic number.

168591 is a deficient number, since it is larger than the sum of its proper divisors (56201).

168591 is an equidigital number, since it uses as much as digits as its factorization.

168591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56200.

The product of its digits is 2160, while the sum is 30.

The square root of 168591 is about 410.5983438837. The cubic root of 168591 is about 55.2431111440.

The spelling of 168591 in words is "one hundred sixty-eight thousand, five hundred ninety-one".