Alright, let's work through 78259251 times 80831463 step by step
78259251 × 80831463 = 80831463 × (78259251)
+ 80831463 × 1 yielding 80831463
+ 80831463 × 50 which equals 4041573150
+ 80831463 × 200 producing 16166292600
+ 80831463 × 9000 that results in 727483167000
+ 80831463 × 50000 producing 4041573150000
+ 80831463 × 200000 producing 16166292600000
+ 80831463 × 8000000 producing 646651704000000
+ 80831463 × 70000000 yielding 5658202410000000

= 6325809751614213
