No problem, we've got 3874 and 6420 to multiply
3874 × 6420 = 6420 × (3874)
+ 6420 × 4 what gives us 25680
+ 6420 × 70 which equals 449400
+ 6420 × 800 what gives us 5136000
+ 6420 × 3000 that equals 19260000

= 24871080
