Alright, let's work through 84054907 times 78642754 step by step
84054907 × 78642754 = 78642754 × (84054907)
+ 78642754 × 7 which equals 550499278
+ 78642754 × 00 resulting in 0
+ 78642754 × 900 giving us 70778478600
+ 78642754 × 4000 resulting in 314571016000
+ 78642754 × 50000 that equals 3932137700000
+ 78642754 × 000000 that equals 0
+ 78642754 × 4000000 that is equal 314571016000000
+ 78642754 × 80000000 producing 6291420320000000

= 6610309373693878
