13687139 has 4 divisors (see below), whose sum is σ = 14282256. Its totient is φ = 13092024.

The previous prime is 13687129. The next prime is 13687169. The reversal of 13687139 is 93178631.

13687139 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 13687139 - 2⁴ = 13687123 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13687129) 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, 297524 + ... + 297569.

It is an arithmetic number, because the mean of its divisors is an integer number (3570564).

Almost surely, 2^13687139 is an apocalyptic number.

13687139 is a deficient number, since it is larger than the sum of its proper divisors (595117).

13687139 is an equidigital number, since it uses as much as digits as its factorization.

13687139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 595116.

The product of its digits is 27216, while the sum is 38.

The square root of 13687139 is about 3699.6133581768. The cubic root of 13687139 is about 239.2053521228.

The spelling of 13687139 in words is "thirteen million, six hundred eighty-seven thousand, one hundred thirty-nine".