12539909 has 2 divisors, whose sum is σ = 12539910. Its totient is φ = 12539908.

The previous prime is 12539893. The next prime is 12539939. The reversal of 12539909 is 90993521.

12539909 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7236100 + 5303809 = 2690^2 + 2303^2 .

It is an emirp because it is prime and its reverse (90993521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12539909 - 2⁴ = 12539893 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12539939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6269954 + 6269955.

It is an arithmetic number, because the mean of its divisors is an integer number (6269955).

Almost surely, 2^12539909 is an apocalyptic number.

It is an amenable number.

12539909 is a deficient number, since it is larger than the sum of its proper divisors (1).

12539909 is an equidigital number, since it uses as much as digits as its factorization.

12539909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21870, while the sum is 38.

The square root of 12539909 is about 3541.1733931001. The cubic root of 12539909 is about 232.3261675161.

The spelling of 12539909 in words is "twelve million, five hundred thirty-nine thousand, nine hundred nine".