9898821788 has 24 divisors (see below), whose sum is σ = 18564659232. Its totient is φ = 4606265664.

The previous prime is 9898821731. The next prime is 9898821797. The reversal of 9898821788 is 8871288989.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1450595 + ... + 1457402.

It is an arithmetic number, because the mean of its divisors is an integer number (773527468).

Almost surely, 2^9898821788 is an apocalyptic number.

It is an amenable number.

9898821788 is a deficient number, since it is larger than the sum of its proper divisors (8665837444).

9898821788 is a wasteful number, since it uses less digits than its factorization.

9898821788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2908061 (or 2908059 counting only the distinct ones).

The product of its digits is 37158912, while the sum is 68.

The square root of 9898821788 is about 99492.8227964208. The cubic root of 9898821788 is about 2147.1439841185.

The spelling of 9898821788 in words is "nine billion, eight hundred ninety-eight million, eight hundred twenty-one thousand, seven hundred eighty-eight".