No problem, we've got 8403 and 8391 to multiply
8403 × 8391 = 8391 × (8403)
+ 8391 × 3 that equals 25173
+ 8391 × 00 what gives us 0
+ 8391 × 400 giving us 3356400
+ 8391 × 8000 what gives us 67128000

= 70509573
