19944319789 has 2 divisors, whose sum is σ = 19944319790. Its totient is φ = 19944319788.

The previous prime is 19944319783. The next prime is 19944319807. The reversal of 19944319789 is 98791344991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12261797289 + 7682522500 = 110733^2 + 87650^2 .

It is an emirp because it is prime and its reverse (98791344991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19944319789 - 2⁵ = 19944319757 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19944319789.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19944319783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9972159894 + 9972159895.

It is an arithmetic number, because the mean of its divisors is an integer number (9972159895).

Almost surely, 2^19944319789 is an apocalyptic number.

It is an amenable number.

19944319789 is a deficient number, since it is larger than the sum of its proper divisors (1).

19944319789 is an equidigital number, since it uses as much as digits as its factorization.

19944319789 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17635968, while the sum is 64.

The spelling of 19944319789 in words is "nineteen billion, nine hundred forty-four million, three hundred nineteen thousand, seven hundred eighty-nine".