172145 has 4 divisors (see below), whose sum is σ = 206580. Its totient is φ = 137712.

The previous prime is 172127. The next prime is 172147. The reversal of 172145 is 541271.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 43264 + 128881 = 208^2 + 359^2 .

It is a cyclic number.

It is not a de Polignac number, because 172145 - 2⁸ = 171889 is a prime.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 172145.

It is not an unprimeable number, because it can be changed into a prime (172147) 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 3 ways as a sum of consecutive naturals, for example, 17210 + ... + 17219.

It is an arithmetic number, because the mean of its divisors is an integer number (51645).

2¹⁷²¹⁴⁵ is an apocalyptic number.

It is an amenable number.

172145 is a deficient number, since it is larger than the sum of its proper divisors (34435).

172145 is an equidigital number, since it uses as much as digits as its factorization.

172145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34434.

The product of its digits is 280, while the sum is 20.

The square root of 172145 is about 414.9036032623. The cubic root of 172145 is about 55.6286009536.

The spelling of 172145 in words is "one hundred seventy-two thousand, one hundred forty-five".