A few years ago, you borrowed some money from a private lender but cannot pay it back. You both agreed to a repayment schedule of $540 per month. The lender will charge 1.3% per month interest on the overdue balance.

If the current balance of the loan is $16,400, how long will it take you to pay off this loan? (Do not round intermediate calculations. Ensure to round up the final answer to the nearest whole number.)