Alright, let's work through 1864 times 7871 step by step
1864 × 7871 = 7871 × (1864)
+ 7871 × 4 yielding 31484
+ 7871 × 60 what gives us 472260
+ 7871 × 800 that results in 6296800
+ 7871 × 1000 that is equal 7871000

= 14671544
