Alright, let's work through 3669 times 5817 step by step
3669 × 5817 = 5817 × (3669)
+ 5817 × 9 what gives us 52353
+ 5817 × 60 giving us 349020
+ 5817 × 600 that results in 3490200
+ 5817 × 3000 giving us 17451000

= 21342573
