844412809 has 2 divisors, whose sum is σ = 844412810. Its totient is φ = 844412808.

The previous prime is 844412791. The next prime is 844412819. The reversal of 844412809 is 908214448.

It is a happy number.

844412809 is digitally balanced in base 2, 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., 431185225 + 413227584 = 20765^2 + 20328^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-844412809 is a prime.

It is not a weakly prime, because it can be changed into another prime (844412819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 422206404 + 422206405.

It is an arithmetic number, because the mean of its divisors is an integer number (422206405).

Almost surely, 2^844412809 is an apocalyptic number.

It is an amenable number.

844412809 is a deficient number, since it is larger than the sum of its proper divisors (1).

844412809 is an equidigital number, since it uses as much as digits as its factorization.

844412809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 73728, while the sum is 40.

The square root of 844412809 is about 29058.7819600203. The cubic root of 844412809 is about 945.1881558474.

The spelling of 844412809 in words is "eight hundred forty-four million, four hundred twelve thousand, eight hundred nine".