Alright, let's work through 1813 times 3851 step by step
1813 × 3851 = 3851 × (1813)
+ 3851 × 3 that is equal 11553
+ 3851 × 10 yielding 38510
+ 3851 × 800 giving us 3080800
+ 3851 × 1000 resulting in 3851000

= 6981863
