Alright, let's work through 80100145 times 65218049 step by step
80100145 × 65218049 = 65218049 × (80100145)
+ 65218049 × 5 that is equal 326090245
+ 65218049 × 40 yielding 2608721960
+ 65218049 × 100 resulting in 6521804900
+ 65218049 × 0000 that results in 0
+ 65218049 × 00000 giving us 0
+ 65218049 × 100000 which equals 6521804900000
+ 65218049 × 0000000 which equals 0
+ 65218049 × 80000000 that results in 5217443920000000

= 5223975181517105
