19998764519 has 2 divisors, whose sum is σ = 19998764520. Its totient is φ = 19998764518.

The previous prime is 19998764503. The next prime is 19998764551. The reversal of 19998764519 is 91546789991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19998764519 - 2⁴ = 19998764503 is a prime.

It is a super-2 number, since 2×19998764519² (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 (19998766519) 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, 9999382259 + 9999382260.

It is an arithmetic number, because the mean of its divisors is an integer number (9999382260).

Almost surely, 2^19998764519 is an apocalyptic number.

19998764519 is a deficient number, since it is larger than the sum of its proper divisors (1).

19998764519 is an equidigital number, since it uses as much as digits as its factorization.

19998764519 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 44089920, while the sum is 68.

The spelling of 19998764519 in words is "nineteen billion, nine hundred ninety-eight million, seven hundred sixty-four thousand, five hundred nineteen".