Alright, let's work through 6728 times 3123 step by step
6728 × 3123 = 3123 × (6728)
+ 3123 × 8 resulting in 24984
+ 3123 × 20 giving us 62460
+ 3123 × 700 that equals 2186100
+ 3123 × 6000 yielding 18738000

= 21011544
