Alright, let's work through 2184 times 7780 step by step
2184 × 7780 = 7780 × (2184)
+ 7780 × 4 giving us 31120
+ 7780 × 80 producing 622400
+ 7780 × 100 what gives us 778000
+ 7780 × 2000 resulting in 15560000

= 16991520
