12866 ÷ 8 = 1608 R2
Alright, let's work through the division of 12866 by 8 step by step.

Step 1:
8 goes into 1 0 times with a remainder of 1.
Write down 0 as next digit of of the result. 
Result so far: 0
Subtract 0 from 1 to get 1.
Bring next digit (2) of the dividend behind the 1 and repeat the process: 12 / 8

Step 2:
8 goes into 12 1 times with a remainder of 4.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 8 from 12 to get 4.
Bring next digit (8) of the dividend behind the 4 and repeat the process: 48 / 8

Step 3:
8 goes into 48 6 times with a remainder of 0.
Write down 6 as next digit of of the result. 
Result so far: 16
Subtract 48 from 48 to get 0.
Bring next digit (6) of the dividend behind the 0 and repeat the process: 6 / 8

Step 4:
8 goes into 6 0 times with a remainder of 6.
Write down 0 as next digit of of the result. 
Result so far: 160
Subtract 0 from 6 to get 6.
Bring next digit (6) of the dividend behind the 6 and repeat the process: 66 / 8

Step 5:
8 goes into 66 8 times with a remainder of 2.
Write down 8 as next digit of of the result. 
Result so far: 1608
Subtract 64 from 66 to get 2.

The final result is 1608 with a remainder of 2.