9900000000 has 486 divisors, whose sum is σ = 38923808196. Its totient is φ = 2400000000.

The previous prime is 9899999987. The next prime is 9900000001. The reversal of 9900000000 is 99.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (9900000001) by changing a digit.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 899999995 + ... + 900000005.

Almost surely, 2^9900000000 is an apocalyptic number.

9900000000 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9900000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19461904098).

9900000000 is an abundant number, since it is smaller than the sum of its proper divisors (29023808196).

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

9900000000 is an frugal number, since it uses more digits than its factorization.

9900000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73 (or 21 counting only the distinct ones).

The product of its (nonzero) digits is 81, while the sum is 18.

The square root of 9900000000 is about 99498.7437106620. The cubic root of 9900000000 is about 2147.2291690189.

Adding to 9900000000 its reverse (99), we get a palindrome (9900000099).

Multiplying 9900000000 by its reverse (99), we get a square (980100000000 = 990000²).

9900000000 divided by its reverse (99) gives a 8-th power (100000000 = 10⁸).

It can be divided in two parts, 9 and 900000000, that multiplied together give a 4-th power (8100000000 = 300⁴).

The spelling of 9900000000 in words is "nine billion, nine hundred million", and thus it is an aban number.