86859 ÷ 9 = 9651 R0
Alright, let's work through the division of 86859 by 9 step by step.

Step 1:
9 goes into 8 0 times with a remainder of 8.
Write down 0 as next digit of of the result. 
Result so far: 0
Subtract 0 from 8 to get 8.
Bring next digit (6) of the dividend behind the 8 and repeat the process: 86 / 9

Step 2:
9 goes into 86 9 times with a remainder of 5.
Write down 9 as next digit of of the result. 
Result so far: 9
Subtract 81 from 86 to get 5.
Bring next digit (8) of the dividend behind the 5 and repeat the process: 58 / 9

Step 3:
9 goes into 58 6 times with a remainder of 4.
Write down 6 as next digit of of the result. 
Result so far: 96
Subtract 54 from 58 to get 4.
Bring next digit (5) of the dividend behind the 4 and repeat the process: 45 / 9

Step 4:
9 goes into 45 5 times with a remainder of 0.
Write down 5 as next digit of of the result. 
Result so far: 965
Subtract 45 from 45 to get 0.
Bring next digit (9) of the dividend behind the 0 and repeat the process: 9 / 9

Step 5:
9 goes into 9 1 times with a remainder of 0.
Write down 1 as next digit of of the result. 
Result so far: 9651
Subtract 9 from 9 to get 0.

The final result is 9651 with a remainder of 0.