No problem, we've got 18276304 and 21580128 to multiply
18276304 × 21580128 = 21580128 × (18276304)
+ 21580128 × 4 what gives us 86320512
+ 21580128 × 00 yielding 0
+ 21580128 × 300 that results in 6474038400
+ 21580128 × 6000 which equals 129480768000
+ 21580128 × 70000 yielding 1510608960000
+ 21580128 × 200000 yielding 4316025600000
+ 21580128 × 8000000 what gives us 172641024000000
+ 21580128 × 10000000 which equals 215801280000000

= 394404979686912
