442815809 has 2 divisors, whose sum is σ = 442815810. Its totient is φ = 442815808.

The previous prime is 442815773. The next prime is 442815833. The reversal of 442815809 is 908518244.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 427331584 + 15484225 = 20672^2 + 3935^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-442815809 is a prime.

It is not a weakly prime, because it can be changed into another prime (442815869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 221407904 + 221407905.

It is an arithmetic number, because the mean of its divisors is an integer number (221407905).

Almost surely, 2^442815809 is an apocalyptic number.

It is an amenable number.

442815809 is a deficient number, since it is larger than the sum of its proper divisors (1).

442815809 is an equidigital number, since it uses as much as digits as its factorization.

442815809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 92160, while the sum is 41.

The square root of 442815809 is about 21043.1891356800. The cubic root of 442815809 is about 762.2095263377.

The spelling of 442815809 in words is "four hundred forty-two million, eight hundred fifteen thousand, eight hundred nine".