Alright, let's work through 3777 times 5581 step by step
3777 × 5581 = 5581 × (3777)
+ 5581 × 7 what gives us 39067
+ 5581 × 70 that is equal 390670
+ 5581 × 700 yielding 3906700
+ 5581 × 3000 that results in 16743000

= 21079437
