23989 ÷ 6 = 3998 R1
Alright, let's work through the division of 23989 by 6 step by step.

Step 1:
6 goes into 2 0 times with a remainder of 2.
Write down 0 as next digit of of the result. 
Result so far: 0
Subtract 0 from 2 to get 2.
Bring next digit (3) of the dividend behind the 2 and repeat the process: 23 / 6

Step 2:
6 goes into 23 3 times with a remainder of 5.
Write down 3 as next digit of of the result. 
Result so far: 3
Subtract 18 from 23 to get 5.
Bring next digit (9) of the dividend behind the 5 and repeat the process: 59 / 6

Step 3:
6 goes into 59 9 times with a remainder of 5.
Write down 9 as next digit of of the result. 
Result so far: 39
Subtract 54 from 59 to get 5.
Bring next digit (8) of the dividend behind the 5 and repeat the process: 58 / 6

Step 4:
6 goes into 58 9 times with a remainder of 4.
Write down 9 as next digit of of the result. 
Result so far: 399
Subtract 54 from 58 to get 4.
Bring next digit (9) of the dividend behind the 4 and repeat the process: 49 / 6

Step 5:
6 goes into 49 8 times with a remainder of 1.
Write down 8 as next digit of of the result. 
Result so far: 3998
Subtract 48 from 49 to get 1.

The final result is 3998 with a remainder of 1.