Alright, let's work through 63997792 times 21483117 step by step
63997792 × 21483117 = 21483117 × (63997792)
+ 21483117 × 2 that equals 42966234
+ 21483117 × 90 resulting in 1933480530
+ 21483117 × 700 that equals 15038181900
+ 21483117 × 7000 producing 150381819000
+ 21483117 × 90000 producing 1933480530000
+ 21483117 × 900000 resulting in 19334805300000
+ 21483117 × 3000000 that is equal 64449351000000
+ 21483117 × 60000000 what gives us 1288987020000000

= 1374872053277664
