Alright, let's work through 8644 times 663 step by step
8644 × 663 = 663 × (8644)
+ 663 × 4 yielding 2652
+ 663 × 40 that equals 26520
+ 663 × 600 that results in 397800
+ 663 × 8000 that equals 5304000

= 5730972
