991332 has 48 divisors (see below), whose sum is σ = 2627520. Its totient is φ = 323136.

The previous prime is 991327. The next prime is 991343. The reversal of 991332 is 233199.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 991296 and 991305.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 991332.

It is an unprimeable number.

991332 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7168 + ... + 7304.

It is an arithmetic number, because the mean of its divisors is an integer number (54740).

2⁹⁹¹³³² 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 991332, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1313760).

991332 is an abundant number, since it is smaller than the sum of its proper divisors (1636188).

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

991332 is a wasteful number, since it uses less digits than its factorization.

991332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217 (or 209 counting only the distinct ones).

The product of its digits is 1458, while the sum is 27.

The square root of 991332 is about 995.6565672962. The cubic root of 991332 is about 99.7102277984.

It can be divided in two parts, 99 and 1332, that added together give a triangular number (1431 = T₅₃).

The spelling of 991332 in words is "nine hundred ninety-one thousand, three hundred thirty-two".