19383808781 has 2 divisors, whose sum is σ = 19383808782. Its totient is φ = 19383808780.

The previous prime is 19383808757. The next prime is 19383808783. The reversal of 19383808781 is 18780838391.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19172833156 + 210975625 = 138466^2 + 14525^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19383808781 is a prime.

It is a super-2 number, since 2×19383808781² (a number of 21 digits) contains 22 as substring.

Together with 19383808783, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19383808783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9691904390 + 9691904391.

It is an arithmetic number, because the mean of its divisors is an integer number (9691904391).

Almost surely, 2^19383808781 is an apocalyptic number.

It is an amenable number.

19383808781 is a deficient number, since it is larger than the sum of its proper divisors (1).

19383808781 is an equidigital number, since it uses as much as digits as its factorization.

19383808781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2322432, while the sum is 56.

The spelling of 19383808781 in words is "nineteen billion, three hundred eighty-three million, eight hundred eight thousand, seven hundred eighty-one".