Let's calculate 8638 x 8330
8638 × 8330 = 8330 × (8638)
+ 8330 × 8 what gives us 66640
+ 8330 × 30 giving us 249900
+ 8330 × 600 that equals 4998000
+ 8330 × 8000 that results in 66640000

= 71954540
