No problem, we've got 4142 and 1638 to multiply
4142 × 1638 = 1638 × (4142)
+ 1638 × 2 what gives us 3276
+ 1638 × 40 which equals 65520
+ 1638 × 100 that equals 163800
+ 1638 × 4000 what gives us 6552000

= 6784596
