Alright, let's work through 82645439 times 54345697 step by step
82645439 × 54345697 = 54345697 × (82645439)
+ 54345697 × 9 what gives us 489111273
+ 54345697 × 30 resulting in 1630370910
+ 54345697 × 400 resulting in 21738278800
+ 54345697 × 5000 producing 271728485000
+ 54345697 × 40000 giving us 2173827880000
+ 54345697 × 600000 producing 32607418200000
+ 54345697 × 2000000 producing 108691394000000
+ 54345697 × 80000000 giving us 4347655760000000

= 4491423986325983
