172189 has 4 divisors (see below), whose sum is σ = 173020. Its totient is φ = 171360.

The previous prime is 172181. The next prime is 172199. The reversal of 172189 is 981271.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 66564 + 105625 = 258^2 + 325^2 .

It is a cyclic number.

It is not a de Polignac number, because 172189 - 2³ = 172181 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172181) 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, 199 + ... + 619.

It is an arithmetic number, because the mean of its divisors is an integer number (43255).

2¹⁷²¹⁸⁹ is an apocalyptic number.

It is an amenable number.

172189 is a deficient number, since it is larger than the sum of its proper divisors (831).

172189 is an equidigital number, since it uses as much as digits as its factorization.

172189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 830.

The product of its digits is 1008, while the sum is 28.

The square root of 172189 is about 414.9566242392. The cubic root of 172189 is about 55.6333400784.

It can be divided in two parts, 172 and 189, that added together give a square (361 = 19²).

The spelling of 172189 in words is "one hundred seventy-two thousand, one hundred eighty-nine".