19768239221 has 2 divisors, whose sum is σ = 19768239222. Its totient is φ = 19768239220.

The previous prime is 19768239167. The next prime is 19768239233. The reversal of 19768239221 is 12293286791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18315562225 + 1452676996 = 135335^2 + 38114^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19768239221 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19768239221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19768239721) 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, 9884119610 + 9884119611.

It is an arithmetic number, because the mean of its divisors is an integer number (9884119611).

Almost surely, 2^19768239221 is an apocalyptic number.

It is an amenable number.

19768239221 is a deficient number, since it is larger than the sum of its proper divisors (1).

19768239221 is an equidigital number, since it uses as much as digits as its factorization.

19768239221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 653184, while the sum is 50.

The spelling of 19768239221 in words is "nineteen billion, seven hundred sixty-eight million, two hundred thirty-nine thousand, two hundred twenty-one".