13878139 has 4 divisors (see below), whose sum is σ = 15139800. Its totient is φ = 12616480.

The previous prime is 13878133. The next prime is 13878149. The reversal of 13878139 is 93187831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93187831 = 11 ⋅8471621.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13878139 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13878133) 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, 630814 + ... + 630835.

It is an arithmetic number, because the mean of its divisors is an integer number (3784950).

Almost surely, 2^13878139 is an apocalyptic number.

13878139 is a deficient number, since it is larger than the sum of its proper divisors (1261661).

13878139 is a wasteful number, since it uses less digits than its factorization.

13878139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1261660.

The product of its digits is 36288, while the sum is 40.

The square root of 13878139 is about 3725.3374343809. The cubic root of 13878139 is about 240.3128962872.

The spelling of 13878139 in words is "thirteen million, eight hundred seventy-eight thousand, one hundred thirty-nine".