The Illusive Pin Number

I know the first and last numbers and the two middle numbers. I just can't seem to string them along in the proper sequence. Not without the little piece of paper at the bottom of my purse that has my dad's Subway order on it and a phone number of whom, I know not. It's not like I can't memorize things, it's just that I haven't taken the time to commit those four little numbers to memory. I've been busy and it's always been at the bottom of my purse that today I decided needs cleaned out. There are 67 grocery lists in there, 38 coupons and 23 receipts, give or take. Usually when the purse gets this unorganized, I get a new one. Same with the checking account, hence the new pin number.
Every year a new purse and every 3 to 5 years I have to tell the husband the checkbook is beyond hope and we must start again. The poor guy looks over his newspaper and says, "How much is it costing us this time?"
"The purse or the checking account?" Ha!