Alright, let's work through 1287780 times 28403421 step by step
1287780 × 28403421 = 28403421 × (1287780)
+ 28403421 × 0 which equals 0
+ 28403421 × 80 resulting in 2272273680
+ 28403421 × 700 giving us 19882394700
+ 28403421 × 7000 giving us 198823947000
+ 28403421 × 80000 what gives us 2272273680000
+ 28403421 × 200000 that is equal 5680684200000
+ 28403421 × 1000000 what gives us 28403421000000

= 36577357495380
