Alright, let's work through 86102159 times 76422811 step by step
86102159 × 76422811 = 76422811 × (86102159)
+ 76422811 × 9 yielding 687805299
+ 76422811 × 50 yielding 3821140550
+ 76422811 × 100 that results in 7642281100
+ 76422811 × 2000 that equals 152845622000
+ 76422811 × 00000 that results in 0
+ 76422811 × 100000 what gives us 7642281100000
+ 76422811 × 6000000 resulting in 458536866000000
+ 76422811 × 80000000 giving us 6113824880000000

= 6580169023948949
