12388889 has 4 divisors (see below), whose sum is σ = 12528180. Its totient is φ = 12249600.

The previous prime is 12388877. The next prime is 12388897. The reversal of 12388889 is 98888321.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2778889 + 9610000 = 1667^2 + 3100^2 .

It is a cyclic number.

It is not a de Polignac number, because 12388889 - 2⁸ = 12388633 is a prime.

It is a Duffinian number.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (12088889) 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, 69512 + ... + 69689.

It is an arithmetic number, because the mean of its divisors is an integer number (3132045).

Almost surely, 2^12388889 is an apocalyptic number.

It is an amenable number.

12388889 is a deficient number, since it is larger than the sum of its proper divisors (139291).

12388889 is an equidigital number, since it uses as much as digits as its factorization.

12388889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139290.

The product of its digits is 221184, while the sum is 47.

The square root of 12388889 is about 3519.7853627743. The cubic root of 12388889 is about 231.3897520006.

The spelling of 12388889 in words is "twelve million, three hundred eighty-eight thousand, eight hundred eighty-nine".