13688439 has 4 divisors (see below), whose sum is σ = 18251256. Its totient is φ = 9125624.

The previous prime is 13688431. The next prime is 13688471. The reversal of 13688439 is 93488631.

It is a happy number.

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 13688439 - 2³ = 13688431 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 13688439.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13688431) 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, 2281404 + ... + 2281409.

It is an arithmetic number, because the mean of its divisors is an integer number (4562814).

Almost surely, 2^13688439 is an apocalyptic number.

13688439 is a deficient number, since it is larger than the sum of its proper divisors (4562817).

13688439 is an equidigital number, since it uses as much as digits as its factorization.

13688439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4562816.

The product of its digits is 124416, while the sum is 42.

The square root of 13688439 is about 3699.7890480404. The cubic root of 13688439 is about 239.2129250985.

The spelling of 13688439 in words is "thirteen million, six hundred eighty-eight thousand, four hundred thirty-nine".