Alright, let's work through 9129 times 7881 step by step
9129 × 7881 = 7881 × (9129)
+ 7881 × 9 what gives us 70929
+ 7881 × 20 which equals 157620
+ 7881 × 100 which equals 788100
+ 7881 × 9000 producing 70929000

= 71945649
