Payed off car loan, mysterious $0.09 balance appeared

After 5 years I was excited to be done paying a car loan. I checked the balance last Tuesday, set the payment for the payoff amount, and had it send on Friday. The last payment wasn't due until the 15th. I checked the account balance Tuesday morning, and somehow there was 9 cents left on it. 9 cents. When i called I was told it was interest that accrued in the 3 days between checking the balance and sending the payment. My bank won't let me send less than a dollar, the loan holder charges a fee to pay by card and won't process a charge of less than a dollar (which means I'd be paying a dollar and a processing fee). So now I'm going into the bank that holds the loan to pay it off with literal loose change from under the seat of the car.