No problem, we've got 20439581 and 7791027 to multiply
20439581 × 7791027 = 7791027 × (20439581)
+ 7791027 × 1 resulting in 7791027
+ 7791027 × 80 what gives us 623282160
+ 7791027 × 500 yielding 3895513500
+ 7791027 × 9000 yielding 70119243000
+ 7791027 × 30000 yielding 233730810000
+ 7791027 × 400000 producing 3116410800000
+ 7791027 × 0000000 resulting in 0
+ 7791027 × 20000000 yielding 155820540000000

= 159245327439687
