991760 has 120 divisors (see below), whose sum is σ = 3053376. Its totient is φ = 295680.

The previous prime is 991751. The next prime is 991777. The reversal of 991760 is 67199.

It is a nialpdrome in base 16.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 991760.

It is an unprimeable number.

991760 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 43109 + ... + 43131.

2⁹⁹¹⁷⁶⁰ 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 991760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1526688).

991760 is an abundant number, since it is smaller than the sum of its proper divisors (2061616).

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

991760 is a wasteful number, since it uses less digits than its factorization.

991760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61 (or 48 counting only the distinct ones).

The product of its (nonzero) digits is 3402, while the sum is 32.

The square root of 991760 is about 995.8714776516. The cubic root of 991760 is about 99.7245754429.

The spelling of 991760 in words is "nine hundred ninety-one thousand, seven hundred sixty".