99891 ÷ 6 = 16648 R3
Let's divide 99891 by 6.

Step 1:
6 goes into 9 1 times with a remainder of 3.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 6 from 9 to get 3.
Bring next digit (9) of the dividend behind the 3 and repeat the process: 39 / 6

Step 2:
6 goes into 39 6 times with a remainder of 3.
Write down 6 as next digit of of the result. 
Result so far: 16
Subtract 36 from 39 to get 3.
Bring next digit (8) of the dividend behind the 3 and repeat the process: 38 / 6

Step 3:
6 goes into 38 6 times with a remainder of 2.
Write down 6 as next digit of of the result. 
Result so far: 166
Subtract 36 from 38 to get 2.
Bring next digit (9) of the dividend behind the 2 and repeat the process: 29 / 6

Step 4:
6 goes into 29 4 times with a remainder of 5.
Write down 4 as next digit of of the result. 
Result so far: 1664
Subtract 24 from 29 to get 5.
Bring next digit (1) of the dividend behind the 5 and repeat the process: 51 / 6

Step 5:
6 goes into 51 8 times with a remainder of 3.
Write down 8 as next digit of of the result. 
Result so far: 16648
Subtract 48 from 51 to get 3.

The final result is 16648 with a remainder of 3.