22565 has 4 divisors (see below), whose sum is σ = 27084. Its totient is φ = 18048.

The previous prime is 22549. The next prime is 22567. The reversal of 22565 is 56522.

It is a happy number.

22565 is nontrivially palindromic in base 4 and base 8.

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 2401 + 20164 = 49^2 + 142^2 .

It is a cyclic number.

It is not a de Polignac number, because 22565 - 2⁴ = 22549 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22567) 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, 2252 + ... + 2261.

It is an arithmetic number, because the mean of its divisors is an integer number (6771).

2²²⁵⁶⁵ is an apocalyptic number.

It is an amenable number.

22565 is a deficient number, since it is larger than the sum of its proper divisors (4519).

22565 is an equidigital number, since it uses as much as digits as its factorization.

22565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4518.

The product of its digits is 600, while the sum is 20.

The square root of 22565 is about 150.2165104108. The cubic root of 22565 is about 28.2582402150.

The spelling of 22565 in words is "twenty-two thousand, five hundred sixty-five".