9990990900 has 144 divisors (see below), whose sum is σ = 35039215680. Its totient is φ = 2422051200.

The previous prime is 9990990871. The next prime is 9990990943. The reversal of 9990990900 is 90990999.

It is a Harshad number since it is a multiple of its sum of digits (54).

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 polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 138499 + ... + 197898.

Almost surely, 2^9990990900 is an apocalyptic number.

9990990900 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

9990990900 is an abundant number, since it is smaller than the sum of its proper divisors (25048224780).

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

9990990900 is a wasteful number, since it uses less digits than its factorization.

9990990900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 336431 (or 336418 counting only the distinct ones).

The product of its (nonzero) digits is 531441, while the sum is 54.

The square root of 9990990900 is about 99954.9443499420. The cubic root of 9990990900 is about 2153.7875117243.

The spelling of 9990990900 in words is "nine billion, nine hundred ninety million, nine hundred ninety thousand, nine hundred".