12440809 has 2 divisors, whose sum is σ = 12440810. Its totient is φ = 12440808.

The previous prime is 12440741. The next prime is 12440819. The reversal of 12440809 is 90804421.

12440809 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6487209 + 5953600 = 2547^2 + 2440^2 .

It is a cyclic number.

It is not a de Polignac number, because 12440809 - 2²³ = 4052201 is a prime.

It is not a weakly prime, because it can be changed into another prime (12440819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6220404 + 6220405.

It is an arithmetic number, because the mean of its divisors is an integer number (6220405).

Almost surely, 2^12440809 is an apocalyptic number.

It is an amenable number.

12440809 is a deficient number, since it is larger than the sum of its proper divisors (1).

12440809 is an equidigital number, since it uses as much as digits as its factorization.

12440809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 12440809 is about 3527.1531012986. The cubic root of 12440809 is about 231.7125415653.

The spelling of 12440809 in words is "twelve million, four hundred forty thousand, eight hundred nine".