8991331998 has 64 divisors (see below), whose sum is σ = 19781044992. Its totient is φ = 2702004480.

The previous prime is 8991331967. The next prime is 8991332003.

8991331998 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9434290 + ... + 9435242.

It is an arithmetic number, because the mean of its divisors is an integer number (309078828).

Almost surely, 2^8991331998 is an apocalyptic number.

8991331998 is an abundant number, since it is smaller than the sum of its proper divisors (10789712994).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

8991331998 is a wasteful number, since it uses less digits than its factorization.

8991331998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2009.

The product of its digits is 3779136, while the sum is 60.

The square root of 8991331998 is about 94822.6344181599. The cubic root of 8991331998 is about 2079.4158244522.

The spelling of 8991331998 in words is "eight billion, nine hundred ninety-one million, three hundred thirty-one thousand, nine hundred ninety-eight".