Alright, let's work through 1986 times 9902 step by step
1986 × 9902 = 9902 × (1986)
+ 9902 × 6 giving us 59412
+ 9902 × 80 resulting in 792160
+ 9902 × 900 that is equal 8911800
+ 9902 × 1000 producing 9902000

= 19665372
