No problem, we've got 1640 and 5180 to multiply
1640 × 5180 = 5180 × (1640)
+ 5180 × 0 giving us 0
+ 5180 × 40 that equals 207200
+ 5180 × 600 which equals 3108000
+ 5180 × 1000 yielding 5180000

= 8495200
