No problem, we've got 8491 and 5639 to multiply
8491 × 5639 = 5639 × (8491)
+ 5639 × 1 what gives us 5639
+ 5639 × 90 yielding 507510
+ 5639 × 400 which equals 2255600
+ 5639 × 8000 giving us 45112000

= 47880749
