12782389 has 4 divisors (see below), whose sum is σ = 12803724. Its totient is φ = 12761056.

The previous prime is 12782377. The next prime is 12782431. The reversal of 12782389 is 98328721.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98328721 = 37 ⋅2657533.

It can be written as a sum of positive squares in 2 ways, for example, as 321489 + 12460900 = 567^2 + 3530^2 .

It is a cyclic number.

It is not a de Polignac number, because 12782389 - 2⁹ = 12781877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12782339) by changing a digit.

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

It is an upside-down number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9742 + ... + 10975.

It is an arithmetic number, because the mean of its divisors is an integer number (3200931).

Almost surely, 2^12782389 is an apocalyptic number.

It is an amenable number.

12782389 is a deficient number, since it is larger than the sum of its proper divisors (21335).

12782389 is an equidigital number, since it uses as much as digits as its factorization.

12782389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21334.

The product of its digits is 48384, while the sum is 40.

The square root of 12782389 is about 3575.2467047744. The cubic root of 12782389 is about 233.8140888257.

The spelling of 12782389 in words is "twelve million, seven hundred eighty-two thousand, three hundred eighty-nine".