28173 has 4 divisors (see below), whose sum is σ = 37568. Its totient is φ = 18780.

The previous prime is 28163. The next prime is 28181. The reversal of 28173 is 37182.

28173 is digitally balanced in base 4, 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 a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 28173 - 2⁶ = 28109 is a prime.

It is a D-number.

It is a Duffinian number.

It is a nialpdrome in base 13 and base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28123) 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, 4693 + ... + 4698.

It is an arithmetic number, because the mean of its divisors is an integer number (9392).

2²⁸¹⁷³ is an apocalyptic number.

It is an amenable number.

28173 is a deficient number, since it is larger than the sum of its proper divisors (9395).

28173 is an equidigital number, since it uses as much as digits as its factorization.

28173 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9394.

The product of its digits is 336, while the sum is 21.

The square root of 28173 is about 167.8481456555. The cubic root of 28173 is about 30.4283006308.

Subtracting 28173 from its reverse (37182), we obtain a palindrome (9009).

The spelling of 28173 in words is "twenty-eight thousand, one hundred seventy-three".