No problem, we've got 8421 and 8634 to multiply
8421 × 8634 = 8634 × (8421)
+ 8634 × 1 that is equal 8634
+ 8634 × 20 that equals 172680
+ 8634 × 400 giving us 3453600
+ 8634 × 8000 that is equal 69072000

= 72706914
