No problem, we've got 4379 and 870 to multiply
4379 × 870 = 870 × (4379)
+ 870 × 9 giving us 7830
+ 870 × 70 what gives us 60900
+ 870 × 300 which equals 261000
+ 870 × 4000 what gives us 3480000

= 3809730
