23539 has 2 divisors, whose sum is σ = 23540. Its totient is φ = 23538.

The previous prime is 23537. The next prime is 23549. The reversal of 23539 is 93532.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 23539 - 2¹ = 23537 is a prime.

Together with 23537, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (23531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11769 + 11770.

It is an arithmetic number, because the mean of its divisors is an integer number (11770).

2²³⁵³⁹ is an apocalyptic number.

23539 is a deficient number, since it is larger than the sum of its proper divisors (1).

23539 is an equidigital number, since it uses as much as digits as its factorization.

23539 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 810, while the sum is 22.

The square root of 23539 is about 153.4242484094. The cubic root of 23539 is about 28.6591080366.

The spelling of 23539 in words is "twenty-three thousand, five hundred thirty-nine".