12688139 has 4 divisors (see below), whose sum is σ = 12983256. Its totient is φ = 12393024.

The previous prime is 12688133. The next prime is 12688141. The reversal of 12688139 is 93188621.

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 12688139 - 2¹² = 12684043 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12688133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 147494 + ... + 147579.

It is an arithmetic number, because the mean of its divisors is an integer number (3245814).

Almost surely, 2^12688139 is an apocalyptic number.

12688139 is a deficient number, since it is larger than the sum of its proper divisors (295117).

12688139 is an equidigital number, since it uses as much as digits as its factorization.

12688139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295116.

The product of its digits is 20736, while the sum is 38.

The square root of 12688139 is about 3562.0414090799. The cubic root of 12688139 is about 233.2380002841.

The spelling of 12688139 in words is "twelve million, six hundred eighty-eight thousand, one hundred thirty-nine".