26Eki
Why are 5-digit PIN-codes so rare?
In case you haven’t noticed, 5-digit PIN-codes are incredibly rare, with their 4-digit and 6-digit counterparts being profusely more common.
In fact, I’d be impressed if you can name a single popular system that uses one.
Why was five skipped?
My only guess would be that five isn’t the more usable or secure number.