Alright, let's work through 8151 times 3890 step by step
8151 × 3890 = 3890 × (8151)
+ 3890 × 1 which equals 3890
+ 3890 × 50 what gives us 194500
+ 3890 × 100 yielding 389000
+ 3890 × 8000 yielding 31120000

= 31707390
