9990999991000 has 192 divisors, whose sum is σ = 27828378658080. Its totient is φ = 3345822547200.

The previous prime is 9990999990947. The next prime is 9990999991009. The reversal of 9990999991000 is 1999990999.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9990999991009) by changing a digit.

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, 263907 + ... + 4477906.

Almost surely, 2^{9990999991000} 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 9990999991000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13914189329040).

9990999991000 is an abundant number, since it is smaller than the sum of its proper divisors (17837378667080).

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

9990999991000 is a wasteful number, since it uses less digits than its factorization.

9990999991000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4741891 (or 4741870 counting only the distinct ones).

The product of its (nonzero) digits is 43046721, while the sum is 73.

The spelling of 9990999991000 in words is "nine trillion, nine hundred ninety billion, nine hundred ninety-nine million, nine hundred ninety-one thousand".