Alright, let's work through 9984 times 1371 step by step
9984 × 1371 = 1371 × (9984)
+ 1371 × 4 producing 5484
+ 1371 × 80 yielding 109680
+ 1371 × 900 that is equal 1233900
+ 1371 × 9000 that equals 12339000

= 13688064
