442991819 has 2 divisors, whose sum is σ = 442991820. Its totient is φ = 442991818.

The previous prime is 442991737. The next prime is 442991867. The reversal of 442991819 is 918199244.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 442991819 - 2¹² = 442987723 is a prime.

It is a super-2 number, since 2×442991819² = 392483503401857522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (442990819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 221495909 + 221495910.

It is an arithmetic number, because the mean of its divisors is an integer number (221495910).

Almost surely, 2^442991819 is an apocalyptic number.

442991819 is a deficient number, since it is larger than the sum of its proper divisors (1).

442991819 is an equidigital number, since it uses as much as digits as its factorization.

442991819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 186624, while the sum is 47.

The square root of 442991819 is about 21047.3708334319. The cubic root of 442991819 is about 762.3105003959.

The spelling of 442991819 in words is "four hundred forty-two million, nine hundred ninety-one thousand, eight hundred nineteen".