991128852 has 96 divisors (see below), whose sum is σ = 2950348800. Its totient is φ = 281861856.

The previous prime is 991128851. The next prime is 991128871. The reversal of 991128852 is 258821199.

991128852 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 991128798 and 991128807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991128851) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 165649 + ... + 171527.

It is an arithmetic number, because the mean of its divisors is an integer number (30732800).

Almost surely, 2^991128852 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 991128852, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1475174400).

991128852 is an abundant number, since it is smaller than the sum of its proper divisors (1959219948).

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

991128852 is a wasteful number, since it uses less digits than its factorization.

991128852 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6122 (or 6114 counting only the distinct ones).

The product of its digits is 103680, while the sum is 45.

The square root of 991128852 is about 31482.1989702117. The cubic root of 991128852 is about 997.0341631746.

The spelling of 991128852 in words is "nine hundred ninety-one million, one hundred twenty-eight thousand, eight hundred fifty-two".