Alright, let's work through 1239 times 6352 step by step
1239 × 6352 = 6352 × (1239)
+ 6352 × 9 that results in 57168
+ 6352 × 30 yielding 190560
+ 6352 × 200 resulting in 1270400
+ 6352 × 1000 resulting in 6352000

= 7870128
