990900000 has 288 divisors, whose sum is σ = 3622268160. Its totient is φ = 263520000.

The previous prime is 990899999. The next prime is 990900019. The reversal of 990900000 is 9099.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (27).

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

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 2699817 + ... + 2700183.

It is an arithmetic number, because the mean of its divisors is an integer number (12577320).

Almost surely, 2^990900000 is an apocalyptic number.

990900000 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 990900000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1811134080).

990900000 is an abundant number, since it is smaller than the sum of its proper divisors (2631368160).

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

990900000 is an equidigital number, since it uses as much as digits as its factorization.

990900000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 411 (or 377 counting only the distinct ones).

The product of its (nonzero) digits is 729, while the sum is 27.

The square root of 990900000 is about 31478.5641349792. The cubic root of 990900000 is about 996.9574187547.

Adding to 990900000 its reverse (9099), we get a palindrome (990909099).

The spelling of 990900000 in words is "nine hundred ninety million, nine hundred thousand".