99998989 has 8 divisors (see below), whose sum is σ = 104474520. Its totient is φ = 95592000.

The previous prime is 99998971. The next prime is 99998999. The reversal of 99998989 is 98989999.

It can be written as a sum of positive squares in 4 ways, for example, as 41705764 + 58293225 = 6458^2 + 7635^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 99998989 - 2¹⁷ = 99867917 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99998909) 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 in 7 ways as a sum of consecutive naturals, for example, 14142 + ... + 19999.

It is an arithmetic number, because the mean of its divisors is an integer number (13059315).

Almost surely, 2^99998989 is an apocalyptic number.

It is an amenable number.

99998989 is a deficient number, since it is larger than the sum of its proper divisors (4475531).

99998989 is a wasteful number, since it uses less digits than its factorization.

99998989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34271.

The product of its digits is 34012224, while the sum is 70.

The square root of 99998989 is about 9999.9494498722. The cubic root of 99998989 is about 464.1573191406.

The spelling of 99998989 in words is "ninety-nine million, nine hundred ninety-eight thousand, nine hundred eighty-nine".