Alright, let's work through 2644 times 4380 step by step
2644 × 4380 = 4380 × (2644)
+ 4380 × 4 producing 17520
+ 4380 × 40 which equals 175200
+ 4380 × 600 what gives us 2628000
+ 4380 × 2000 which equals 8760000

= 11580720
