9989899 is nontrivially palindromic in base 10.
9989899 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.
It is a weak prime.
It is a palprime.
It is a cyclic number.
Almost surely, 29989899 is an apocalyptic number.
9989899 is an equidigital number, since it uses as much as digits as its factorization.
9989899 is an evil number, because the sum of its binary digits is even.
The square root of 9989899 is about 3160.6801483225. The cubic root of 9989899 is about 215.3709047493.
The spelling of 9989899 in words is "nine million, nine hundred eighty-nine thousand, eight hundred ninety-nine".