Alright, let's work through 6791 times 635 step by step
6791 × 635 = 635 × (6791)
+ 635 × 1 that results in 635
+ 635 × 90 that equals 57150
+ 635 × 700 which equals 444500
+ 635 × 6000 resulting in 3810000

= 4312285
