13539439 has 2 divisors, whose sum is σ = 13539440. Its totient is φ = 13539438.

The previous prime is 13539437. The next prime is 13539451. The reversal of 13539439 is 93493531.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 13539439 - 2¹ = 13539437 is a prime.

Together with 13539437, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 13539398 and 13539407.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13539437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6769719 + 6769720.

It is an arithmetic number, because the mean of its divisors is an integer number (6769720).

Almost surely, 2^13539439 is an apocalyptic number.

13539439 is a deficient number, since it is larger than the sum of its proper divisors (1).

13539439 is an equidigital number, since it uses as much as digits as its factorization.

13539439 is an evil number, because the sum of its binary digits is even.

The product of its digits is 43740, while the sum is 37.

The square root of 13539439 is about 3679.5976682241. The cubic root of 13539439 is about 238.3418046228.

The spelling of 13539439 in words is "thirteen million, five hundred thirty-nine thousand, four hundred thirty-nine".