Alright, let's work through 51812494 times 80878190 step by step
51812494 × 80878190 = 80878190 × (51812494)
+ 80878190 × 4 that equals 323512760
+ 80878190 × 90 producing 7279037100
+ 80878190 × 400 yielding 32351276000
+ 80878190 × 2000 that results in 161756380000
+ 80878190 × 10000 what gives us 808781900000
+ 80878190 × 800000 yielding 64702552000000
+ 80878190 × 1000000 which equals 80878190000000
+ 80878190 × 50000000 that results in 4043909500000000

= 4190500734105860
