Please help me with this question, I'm stuck on it and an explanation or how to use it on the finance calculator will be much help.

Thank you

One of your customers is delinquent on his accounts payable balance. You've mutually agreed to a repayment schedule of $450 per month. You will charge 1.3 percent per month interest on the overdue balance. If the current balance is $18,000, how long will it take for the account to be paid off? (Do not round intermediate calculations and round your answer to 2 decimal places, e.g., 32.16.) Months for account to be paid off months