1. The longest periods of time I've gone nude are the ten days I spend each year at the GNI annual gatherings. The events are held at a campground where almost all everything is provided, so there's no real reason to get dressed to leave the camp. Plus nudity is mandatory except for weather and health reasons.2. I'm not a "full time" nudist, so I get dressed and go to work and other daily activities. But when I'm at home I'm frequently naked.
I can't easily say how long I have gone without being nude. I usually sleep nude, and am around the house nude, and when traveling, business or pleasure, am usually nude when in my hotel room.
During the summer when I was 16, I remember I carried in the trash cans after the garbage was collected, and mowed the lawn, and then stripped off to go swimming in our pool. On Saturday, we left to go to the trailer we kept at a nudist resort and, since I just had to put a bag with my reading materials into the back, I didn't bother dressing and so we left for the resort, me naked in the car and without any clothing along.
We spent a week there, but one of the guys I knew there was picked up by his uncle on the Sunday my folks were leaving, and I was invited Togo with him for a couple of weeks at their farm up in the foothills. So my friend and I got into his uncle's car with his cousin and we went to their farm / ranch. (His cousin also spent his time at home nude, and uncle and cousin had lunch with us at the resort before we all left, his cousin as naked as we were.)
A couple of weeks later, we were dropped off on Saturday at the resort, where we my my parents and then they drove my friend home and we went home on Sunday.
So that is 24 days nude, mostly without any clothes for a over a hundred miles away. I don't remember how long it was after that until I got dressed again.