Alright, let's work through 2790 times 7783 step by step
2790 × 7783 = 7783 × (2790)
+ 7783 × 0 resulting in 0
+ 7783 × 90 resulting in 700470
+ 7783 × 700 which equals 5448100
+ 7783 × 2000 resulting in 15566000

= 21714570
