No problem, we've got 21077393 and 18381207 to multiply
21077393 × 18381207 = 18381207 × (21077393)
+ 18381207 × 3 resulting in 55143621
+ 18381207 × 90 yielding 1654308630
+ 18381207 × 300 giving us 5514362100
+ 18381207 × 7000 that is equal 128668449000
+ 18381207 × 70000 that is equal 1286684490000
+ 18381207 × 000000 resulting in 0
+ 18381207 × 1000000 which equals 18381207000000
+ 18381207 × 20000000 yielding 367624140000000

= 387427923753351
