No problem, we've got 6598 and 8391 to multiply
6598 × 8391 = 8391 × (6598)
+ 8391 × 8 which equals 67128
+ 8391 × 90 giving us 755190
+ 8391 × 500 that is equal 4195500
+ 8391 × 6000 giving us 50346000

= 55363818
