12440389 has 4 divisors (see below), whose sum is σ = 13397356. Its totient is φ = 11483424.

The previous prime is 12440381. The next prime is 12440411. The reversal of 12440389 is 98304421.

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 6477025 + 5963364 = 2545^2 + 2442^2 .

It is a cyclic number.

It is not a de Polignac number, because 12440389 - 2³ = 12440381 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12440389.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12440381) 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, 478464 + ... + 478489.

It is an arithmetic number, because the mean of its divisors is an integer number (3349339).

Almost surely, 2^12440389 is an apocalyptic number.

It is an amenable number.

12440389 is a deficient number, since it is larger than the sum of its proper divisors (956967).

12440389 is an equidigital number, since it uses as much as digits as its factorization.

12440389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 956966.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 12440389 is about 3527.0935626944. The cubic root of 12440389 is about 231.7099340081.

The spelling of 12440389 in words is "twelve million, four hundred forty thousand, three hundred eighty-nine".