Alright, let's work through 6435 times 1321 step by step
6435 × 1321 = 1321 × (6435)
+ 1321 × 5 that is equal 6605
+ 1321 × 30 giving us 39630
+ 1321 × 400 resulting in 528400
+ 1321 × 6000 that results in 7926000

= 8500635
