No problem, we've got 21209609 and 12682619 to multiply
21209609 × 12682619 = 12682619 × (21209609)
+ 12682619 × 9 producing 114143571
+ 12682619 × 00 which equals 0
+ 12682619 × 600 giving us 7609571400
+ 12682619 × 9000 producing 114143571000
+ 12682619 × 00000 that is equal 0
+ 12682619 × 200000 producing 2536523800000
+ 12682619 × 1000000 which equals 12682619000000
+ 12682619 × 20000000 producing 253652380000000

= 268993390085971
