19993830491 has 2 divisors, whose sum is σ = 19993830492. Its totient is φ = 19993830490.

The previous prime is 19993830481. The next prime is 19993830539. The reversal of 19993830491 is 19403839991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19993830491 - 2⁶ = 19993830427 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (19993830421) 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, 9996915245 + 9996915246.

It is an arithmetic number, because the mean of its divisors is an integer number (9996915246).

Almost surely, 2^19993830491 is an apocalyptic number.

19993830491 is a deficient number, since it is larger than the sum of its proper divisors (1).

19993830491 is an equidigital number, since it uses as much as digits as its factorization.

19993830491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1889568, while the sum is 56.

The spelling of 19993830491 in words is "nineteen billion, nine hundred ninety-three million, eight hundred thirty thousand, four hundred ninety-one".