Matching principal and interest method: loan principal: 65,438+0,904,000, assuming annual interest rate: 4.900%, loan term: 30 years, monthly principal and interest payment: 65,438+0,065,438+0,005.04 yuan, and total repayment: 36,378. The interest paid in 1 month is: 7774.67; The first 1 month principal repayment amount is: 2330.37; Since then, the monthly interest repayment amount has decreased and the principal has increased. (without considering the adjustment of interest rate in the middle)