9899889919 has 2 divisors, whose sum is σ = 9899889920. Its totient is φ = 9899889918.

The previous prime is 9899889913. The next prime is 9899889929. The reversal of 9899889919 is 9199889989.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 9899889919 - 2⁵ = 9899889887 is a prime.

It is a super-2 number, since 2×9899889919² (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 (9899889913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4949944959 + 4949944960.

It is an arithmetic number, because the mean of its divisors is an integer number (4949944960).

Almost surely, 2^9899889919 is an apocalyptic number.

9899889919 is a deficient number, since it is larger than the sum of its proper divisors (1).

9899889919 is an equidigital number, since it uses as much as digits as its factorization.

9899889919 is an evil number, because the sum of its binary digits is even.

The product of its digits is 272097792, while the sum is 79.

The square root of 9899889919 is about 99498.1905312855. The cubic root of 9899889919 is about 2147.2212104327.

The spelling of 9899889919 in words is "nine billion, eight hundred ninety-nine million, eight hundred eighty-nine thousand, nine hundred nineteen".