9891994752 has 320 divisors, whose sum is σ = 30420561600. Its totient is φ = 3189528576.

The previous prime is 9891994751. The next prime is 9891994769. The reversal of 9891994752 is 2574991989.

Its product of digits (14696640) is a multiple of the sum of its prime divisors (324).

It is a self number, because there is not a number n which added to its sum of digits gives 9891994752.

It is not an unprimeable number, because it can be changed into a prime (9891994751) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 63006258 + ... + 63006414.

It is an arithmetic number, because the mean of its divisors is an integer number (95064255).

Almost surely, 2^9891994752 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 9891994752, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15210280800).

9891994752 is an abundant number, since it is smaller than the sum of its proper divisors (20528566848).

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

9891994752 is a wasteful number, since it uses less digits than its factorization.

9891994752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 345 (or 324 counting only the distinct ones).

The product of its digits is 14696640, while the sum is 63.

The square root of 9891994752 is about 99458.5076903932. The cubic root of 9891994752 is about 2146.6502553088.

The spelling of 9891994752 in words is "nine billion, eight hundred ninety-one million, nine hundred ninety-four thousand, seven hundred fifty-two".