9991002024 has 80 divisors (see below), whose sum is σ = 28030533300. Its totient is φ = 3324803328.

The previous prime is 9991002013. The next prime is 9991002089. The reversal of 9991002024 is 4202001999.

It is a Cunningham number, because it is equal to 99955²-1.

It can be written as a sum of positive squares in 2 ways, for example, as 9962036100 + 28965924 = 99810^2 + 5382^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 9991002024.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 387322 + ... + 412310.

Almost surely, 2^9991002024 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 9991002024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14015266650).

9991002024 is an abundant number, since it is smaller than the sum of its proper divisors (18039531276).

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

9991002024 is a wasteful number, since it uses less digits than its factorization.

9991002024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25624 (or 25611 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 9991002024 is about 99954.9999949977. Note that the first 5 decimals coincide. The cubic root of 9991002024 is about 2153.7883110685.

The spelling of 9991002024 in words is "nine billion, nine hundred ninety-one million, two thousand, twenty-four".