9999889900 has 288 divisors, whose sum is σ = 29321123328. Its totient is φ = 2858803200.

The previous prime is 9999889877. The next prime is 9999889901. The reversal of 9999889900 is 99889999.

It is a Harshad number since it is a multiple of its sum of digits (70).

It is a zygodrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 9999889900.

It is not an unprimeable number, because it can be changed into a prime (9999889901) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 28328124 + ... + 28328476.

It is an arithmetic number, because the mean of its divisors is an integer number (101809456).

Almost surely, 2^9999889900 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9999889900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14660561664).

9999889900 is an abundant number, since it is smaller than the sum of its proper divisors (19321233428).

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

9999889900 is a wasteful number, since it uses less digits than its factorization.

9999889900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 681 (or 674 counting only the distinct ones).

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

The square root of 9999889900 is about 99999.4494984847. The cubic root of 9999889900 is about 2154.4267832276.

The spelling of 9999889900 in words is "nine billion, nine hundred ninety-nine million, eight hundred eighty-nine thousand, nine hundred".