Alright, let's work through 81193249 times 66837888 step by step
81193249 × 66837888 = 66837888 × (81193249)
+ 66837888 × 9 yielding 601540992
+ 66837888 × 40 resulting in 2673515520
+ 66837888 × 200 that equals 13367577600
+ 66837888 × 3000 yielding 200513664000
+ 66837888 × 90000 giving us 6015409920000
+ 66837888 × 100000 that equals 6683788800000
+ 66837888 × 1000000 which equals 66837888000000
+ 66837888 × 80000000 which equals 5347031040000000

= 5426785283018112
