Alright, let's work through 4161 times 3640 step by step
4161 × 3640 = 3640 × (4161)
+ 3640 × 1 that results in 3640
+ 3640 × 60 giving us 218400
+ 3640 × 100 resulting in 364000
+ 3640 × 4000 yielding 14560000

= 15146040
