Alright, let's work through 8506 times 7740 step by step
8506 × 7740 = 7740 × (8506)
+ 7740 × 6 which equals 46440
+ 7740 × 00 that is equal 0
+ 7740 × 500 what gives us 3870000
+ 7740 × 8000 resulting in 61920000

= 65836440
