No problem, we've got 1557 and 8391 to multiply
1557 × 8391 = 8391 × (1557)
+ 8391 × 7 giving us 58737
+ 8391 × 50 that is equal 419550
+ 8391 × 500 yielding 4195500
+ 8391 × 1000 that results in 8391000

= 13064787
