Alright, let's work through 87720663 times 21129727 step by step
87720663 × 21129727 = 21129727 × (87720663)
+ 21129727 × 3 that results in 63389181
+ 21129727 × 60 yielding 1267783620
+ 21129727 × 600 that equals 12677836200
+ 21129727 × 0000 which equals 0
+ 21129727 × 20000 that equals 422594540000
+ 21129727 × 700000 yielding 14790808900000
+ 21129727 × 7000000 yielding 147908089000000
+ 21129727 × 80000000 that equals 1690378160000000

= 1853513661449001
