91989 ÷ 4 = 22997 R1
Let's divide 91989 by 4.

Step 1:
4 goes into 9 2 times with a remainder of 1.
Write down 2 as next digit of of the result. 
Result so far: 2
Subtract 8 from 9 to get 1.
Bring next digit (1) of the dividend behind the 1 and repeat the process: 11 / 4

Step 2:
4 goes into 11 2 times with a remainder of 3.
Write down 2 as next digit of of the result. 
Result so far: 22
Subtract 8 from 11 to get 3.
Bring next digit (9) of the dividend behind the 3 and repeat the process: 39 / 4

Step 3:
4 goes into 39 9 times with a remainder of 3.
Write down 9 as next digit of of the result. 
Result so far: 229
Subtract 36 from 39 to get 3.
Bring next digit (8) of the dividend behind the 3 and repeat the process: 38 / 4

Step 4:
4 goes into 38 9 times with a remainder of 2.
Write down 9 as next digit of of the result. 
Result so far: 2299
Subtract 36 from 38 to get 2.
Bring next digit (9) of the dividend behind the 2 and repeat the process: 29 / 4

Step 5:
4 goes into 29 7 times with a remainder of 1.
Write down 7 as next digit of of the result. 
Result so far: 22997
Subtract 28 from 29 to get 1.

The final result is 22997 with a remainder of 1.