12438391 has 4 divisors (see below), whose sum is σ = 14215312. Its totient is φ = 10661472.

The previous prime is 12438311. The next prime is 12438403. The reversal of 12438391 is 19383421.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 12438391 - 2⁷ = 12438263 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12438301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 888450 + ... + 888463.

It is an arithmetic number, because the mean of its divisors is an integer number (3553828).

Almost surely, 2^12438391 is an apocalyptic number.

12438391 is a deficient number, since it is larger than the sum of its proper divisors (1776921).

12438391 is an equidigital number, since it uses as much as digits as its factorization.

12438391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1776920.

The product of its digits is 5184, while the sum is 31.

The square root of 12438391 is about 3526.8103152849. The cubic root of 12438391 is about 231.6975286824.

The spelling of 12438391 in words is "twelve million, four hundred thirty-eight thousand, three hundred ninety-one".