No problem, we've got 6996 and 645 to multiply
6996 × 645 = 645 × (6996)
+ 645 × 6 which equals 3870
+ 645 × 90 producing 58050
+ 645 × 900 what gives us 580500
+ 645 × 6000 that results in 3870000

= 4512420
