Alright, let's work through 83821356 times 65942099 step by step
83821356 × 65942099 = 65942099 × (83821356)
+ 65942099 × 6 resulting in 395652594
+ 65942099 × 50 that is equal 3297104950
+ 65942099 × 300 resulting in 19782629700
+ 65942099 × 1000 producing 65942099000
+ 65942099 × 20000 yielding 1318841980000
+ 65942099 × 800000 that equals 52753679200000
+ 65942099 × 3000000 yielding 197826297000000
+ 65942099 × 80000000 giving us 5275367920000000

= 5527356155666244
