Alright, let's work through 1635 times 1220 step by step
1635 × 1220 = 1220 × (1635)
+ 1220 × 5 what gives us 6100
+ 1220 × 30 that results in 36600
+ 1220 × 600 resulting in 732000
+ 1220 × 1000 which equals 1220000

= 1994700
