3 1/2 days once, so that's approx. 84 hours.
I college, I worked 3rd shift 7 days a week 3/4 of the weeks of a month, I'd count 19-23 days in a row of working before a single day off, plus went to 8 hours of classes every day, so I averaged 10 hours of sleep a week. I was also trying to have a girlfriend too, so I would visit her instead of sleeping.
When I did get to sleep, it was anywhere from 1 to 3 hours. Never more.
Glad those days are over.
I have a newborn baby at home now, work 2 jobs and still get a LOT more sleep than I did during college.