23665 has 4 divisors (see below), whose sum is σ = 28404. Its totient is φ = 18928.

The previous prime is 23663. The next prime is 23669. The reversal of 23665 is 56632.

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 6241 + 17424 = 79^2 + 132^2 .

It is a cyclic number.

It is not a de Polignac number, because 23665 - 2¹ = 23663 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23663) 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, 2362 + ... + 2371.

It is an arithmetic number, because the mean of its divisors is an integer number (7101).

2²³⁶⁶⁵ is an apocalyptic number.

It is an amenable number.

23665 is a deficient number, since it is larger than the sum of its proper divisors (4739).

23665 is an equidigital number, since it uses as much as digits as its factorization.

23665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4738.

The product of its digits is 1080, while the sum is 22.

The square root of 23665 is about 153.8343264684. The cubic root of 23665 is about 28.7101527370.

The spelling of 23665 in words is "twenty-three thousand, six hundred sixty-five".