19843423399 has 2 divisors, whose sum is σ = 19843423400. Its totient is φ = 19843423398.

The previous prime is 19843423373. The next prime is 19843423429. The reversal of 19843423399 is 99332434891.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19843423399 - 2⁹ = 19843422887 is a prime.

It is a super-2 number, since 2×19843423399² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19843423339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9921711699 + 9921711700.

It is an arithmetic number, because the mean of its divisors is an integer number (9921711700).

Almost surely, 2^19843423399 is an apocalyptic number.

19843423399 is a deficient number, since it is larger than the sum of its proper divisors (1).

19843423399 is an equidigital number, since it uses as much as digits as its factorization.

19843423399 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5038848, while the sum is 55.

The spelling of 19843423399 in words is "nineteen billion, eight hundred forty-three million, four hundred twenty-three thousand, three hundred ninety-nine".