What is the question? The errormessage says it all, doesn't it?
So it depends what you are going to to with that integral.
You can assign it to a function by typing I(x):= in front and evaluate it numerically.
You may even apply symbolic operations to I(x). So you will be able to see the denominator by evaluating denom(I(x)). Trying to see the nominator (numer(I(x)) will fail again as the expression being too large.
If you really want to just SEE the result, one way would be to use Wolfram Alpha
I tried numer and denom, too, but without factor with no success. (Along with a complex manual parfrac to no avail)
Knowing now thanks your investigations that factor works, we can do without those functions (Think on can omit "max" without disadvantages):