172565 has 4 divisors (see below), whose sum is σ = 207084. Its totient is φ = 138048.

The previous prime is 172561. The next prime is 172573. The reversal of 172565 is 565271.

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 111556 + 61009 = 334^2 + 247^2 .

It is a cyclic number.

It is not a de Polignac number, because 172565 - 2² = 172561 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 (172561) 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, 17252 + ... + 17261.

It is an arithmetic number, because the mean of its divisors is an integer number (51771).

2¹⁷²⁵⁶⁵ is an apocalyptic number.

It is an amenable number.

172565 is a deficient number, since it is larger than the sum of its proper divisors (34519).

172565 is an equidigital number, since it uses as much as digits as its factorization.

172565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34518.

The product of its digits is 2100, while the sum is 26.

The square root of 172565 is about 415.4094365803. The cubic root of 172565 is about 55.6738051650.

It can be divided in two parts, 172 and 565, that added together give a palindrome (737).

The spelling of 172565 in words is "one hundred seventy-two thousand, five hundred sixty-five".