Alright, let's work through 83998647 times 55771367 step by step
83998647 × 55771367 = 55771367 × (83998647)
+ 55771367 × 7 producing 390399569
+ 55771367 × 40 yielding 2230854680
+ 55771367 × 600 yielding 33462820200
+ 55771367 × 8000 producing 446170936000
+ 55771367 × 90000 which equals 5019423030000
+ 55771367 × 900000 that results in 50194230300000
+ 55771367 × 3000000 which equals 167314101000000
+ 55771367 × 80000000 resulting in 4461709360000000

= 4684719369340449
