Alright, let's work through 1678 times 6709 step by step
1678 × 6709 = 6709 × (1678)
+ 6709 × 8 yielding 53672
+ 6709 × 70 what gives us 469630
+ 6709 × 600 which equals 4025400
+ 6709 × 1000 which equals 6709000

= 11257702
