19816441243 has 2 divisors, whose sum is σ = 19816441244. Its totient is φ = 19816441242.

The previous prime is 19816441163. The next prime is 19816441259. The reversal of 19816441243 is 34214461891.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 19816441243 - 2²¹ = 19814344091 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19816441243.

It is not a weakly prime, because it can be changed into another prime (19816441283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9908220621 + 9908220622.

It is an arithmetic number, because the mean of its divisors is an integer number (9908220622).

Almost surely, 2^19816441243 is an apocalyptic number.

19816441243 is a deficient number, since it is larger than the sum of its proper divisors (1).

19816441243 is an equidigital number, since it uses as much as digits as its factorization.

19816441243 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 165888, while the sum is 43.

The spelling of 19816441243 in words is "nineteen billion, eight hundred sixteen million, four hundred forty-one thousand, two hundred forty-three".