Alright, let's work through 8364 times 1641 step by step
8364 × 1641 = 1641 × (8364)
+ 1641 × 4 which equals 6564
+ 1641 × 60 which equals 98460
+ 1641 × 300 yielding 492300
+ 1641 × 8000 that equals 13128000

= 13725324
