13539 has 4 divisors (see below), whose sum is σ = 18056. Its totient is φ = 9024.

The previous prime is 13537. The next prime is 13553. The reversal of 13539 is 93531.

13539 is an esthetic number in base 7 and base 8, because in such bases its adjacent digits differ by 1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93531 = 3 ⋅31177.

It is not a de Polignac number, because 13539 - 2¹ = 13537 is a prime.

It is a D-number.

It is a Duffinian number.

It is a nialpdrome in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13537) 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, 2254 + ... + 2259.

It is an arithmetic number, because the mean of its divisors is an integer number (4514).

2¹³⁵³⁹ is an apocalyptic number.

13539 is a deficient number, since it is larger than the sum of its proper divisors (4517).

13539 is an equidigital number, since it uses as much as digits as its factorization.

13539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4516.

The product of its digits is 405, while the sum is 21.

The square root of 13539 is about 116.3572086293. The cubic root of 13539 is about 23.8339228613.

It can be divided in two parts, 13 and 539, that multiplied together give a palindrome (7007).

The spelling of 13539 in words is "thirteen thousand, five hundred thirty-nine".