No you certainly should not ask that question.
You applied for this job and weren't headhunted. So there were criteria for the position described on the job advert - criteria that the hiring staff clearly feel you meet, at least to a large extent.
You haven't said whether or not the job is at your current university, e.g. the university where you have been working as a fellow until now. Obviously this would have a bearing on your application for a faculty position since you would already be known - at least professionally and to some extent personally - to the faculty there. The fact that you have make the first 'cut' shows that this may have advantaged you. But do not see this as the only possibility: you may also be included as a makeweight, as a sop to 'one of their own' who might sulk were he not at least interviewed, as a comparison candidate to gauge unknown but equally well-qualified candidates, etc.
The foregoing answers detail a shoal of reasons why asking that question would give a bad impression. I agree with many of them, particularly the fact that you should have parsed the job spec, explored the research & teaching profile of the department's groups and considered for yourself the matchability of your own candidacy. That's the prima facie answer: take it or leave it. If you adjudge yourself to have not met these criteria but applied anyway and somehow got a first round interview, then it is not even a question.
That brings me to perhaps the greatest reason for not asking the question. It is that by asking this you are showing yourself to be the sort of person who always tends to look behind the veil. And this naturally says something adverse about your own character and socio-professional outlook - something I daresay that hiring faculty would prefer to avoid: academia already has an ample proportion of such people and their nature does not help collegial relations. While there are times when we all have to lie, few lies/false fronts are constructed for altruistic reasons or towards a happier end state of human relations: they are said for the advantage and satisfaction of the teller.
If I were you, I'd wait till the initial interview was complete and hear some additional criteria that the committee perhaps might not have seen as wise to include in their job advert: it might attract the wrong type of candidate or deter those they might want to hire. For example, in applying for a Research Assistant + PhD programme position once it was said at the interview that the institution would train me in electron microscopy so I could better support existing researchers 9 - 5 Mon - Fri while I could work evenings and weekends on my own project. This training would be superior to that available commercially for ~ £10k - £15k. Obviously, if this were listed in the advert the institution would likely hire someone whose intentions were simply to take the training and then move elsewhere without completing their PhD project.
So go to the first interview even if you don't now see the fit entirely. There may well be more to this job that they can describe in the advert.
And do not ask that dumb question !