No problem, we've got 19905548 and 12418623 to multiply
19905548 × 12418623 = 12418623 × (19905548)
+ 12418623 × 8 what gives us 99348984
+ 12418623 × 40 yielding 496744920
+ 12418623 × 500 producing 6209311500
+ 12418623 × 5000 which equals 62093115000
+ 12418623 × 00000 producing 0
+ 12418623 × 900000 yielding 11176760700000
+ 12418623 × 9000000 that equals 111767607000000
+ 12418623 × 10000000 producing 124186230000000

= 247199496220404
