No problem, we've got 3815 and 1004 to multiply
3815 × 1004 = 1004 × (3815)
+ 1004 × 5 that is equal 5020
+ 1004 × 10 giving us 10040
+ 1004 × 800 producing 803200
+ 1004 × 3000 giving us 3012000

= 3830260
