19981312619 has 2 divisors, whose sum is σ = 19981312620. Its totient is φ = 19981312618.

The previous prime is 19981312613. The next prime is 19981312621. The reversal of 19981312619 is 91621318991.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19981312619 is a prime.

It is a super-2 number, since 2×19981312619² (a number of 21 digits) contains 22 as substring.

Together with 19981312621, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (19981312613) 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, 9990656309 + 9990656310.

It is an arithmetic number, because the mean of its divisors is an integer number (9990656310).

Almost surely, 2^19981312619 is an apocalyptic number.

19981312619 is a deficient number, since it is larger than the sum of its proper divisors (1).

19981312619 is an equidigital number, since it uses as much as digits as its factorization.

19981312619 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 209952, while the sum is 50.

The spelling of 19981312619 in words is "nineteen billion, nine hundred eighty-one million, three hundred twelve thousand, six hundred nineteen".