13538909 has 4 divisors (see below), whose sum is σ = 13975680. Its totient is φ = 13102140.

The previous prime is 13538879. The next prime is 13538923. The reversal of 13538909 is 90983531.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90983531 = 983 ⋅92557.

It is a cyclic number.

It is not a de Polignac number, because 13538909 - 2¹⁶ = 13473373 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13538989) 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, 218339 + ... + 218400.

It is an arithmetic number, because the mean of its divisors is an integer number (3493920).

Almost surely, 2^13538909 is an apocalyptic number.

It is an amenable number.

13538909 is a deficient number, since it is larger than the sum of its proper divisors (436771).

13538909 is an equidigital number, since it uses as much as digits as its factorization.

13538909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 436770.

The product of its (nonzero) digits is 29160, while the sum is 38.

The square root of 13538909 is about 3679.5256487759. The cubic root of 13538909 is about 238.3386946268.

The spelling of 13538909 in words is "thirteen million, five hundred thirty-eight thousand, nine hundred nine".