19804313779 has 2 divisors, whose sum is σ = 19804313780. Its totient is φ = 19804313778.

The previous prime is 19804313729. The next prime is 19804313801. The reversal of 19804313779 is 97731340891.

It is a strong prime.

It is an emirp because it is prime and its reverse (97731340891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19804313779 - 2²¹ = 19802216627 is a prime.

It is not a weakly prime, because it can be changed into another prime (19804313729) 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, 9902156889 + 9902156890.

It is an arithmetic number, because the mean of its divisors is an integer number (9902156890).

Almost surely, 2^19804313779 is an apocalyptic number.

19804313779 is a deficient number, since it is larger than the sum of its proper divisors (1).

19804313779 is an equidigital number, since it uses as much as digits as its factorization.

19804313779 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1143072, while the sum is 52.

The spelling of 19804313779 in words is "nineteen billion, eight hundred four million, three hundred thirteen thousand, seven hundred seventy-nine".