Alright, let's work through 42820299 times 79954311 step by step
42820299 × 79954311 = 79954311 × (42820299)
+ 79954311 × 9 what gives us 719588799
+ 79954311 × 90 what gives us 7195887990
+ 79954311 × 200 what gives us 15990862200
+ 79954311 × 0000 that equals 0
+ 79954311 × 20000 resulting in 1599086220000
+ 79954311 × 800000 yielding 63963448800000
+ 79954311 × 2000000 giving us 159908622000000
+ 79954311 × 40000000 what gives us 3198172440000000

= 3423667503358989
