Alright, let's work through 6400 times 8739 step by step
6400 × 8739 = 8739 × (6400)
+ 8739 × 0 which equals 0
+ 8739 × 00 that is equal 0
+ 8739 × 400 producing 3495600
+ 8739 × 6000 producing 52434000

= 55929600
