How many aneurysms are the most anyone had post stroke? are they operable?

Your questions require more details. Most people have only one aneurysm at a time, sometimes in the abdomen, it can be large.

At your age, 74 yrs., you would be unlikely to have a congenital aneurysm, but if you have high uncontrolled hypertension, you would be at risk for Charcot-Bouchard aneurysms, of which there could be several. These can cause sudden intracranial hemorrhages in specific brain areas, and can be very dangerous. Lesson here is to monitor and control hypertension fully.