Alright, let's work through 81069304 times 20559661 step by step
81069304 × 20559661 = 20559661 × (81069304)
+ 20559661 × 4 that results in 82238644
+ 20559661 × 00 what gives us 0
+ 20559661 × 300 yielding 6167898300
+ 20559661 × 9000 yielding 185036949000
+ 20559661 × 60000 resulting in 1233579660000
+ 20559661 × 000000 which equals 0
+ 20559661 × 1000000 what gives us 20559661000000
+ 20559661 × 80000000 that equals 1644772880000000

= 1666757407745944
