21598 ÷ 6 = 3599 R4
No problem, we've got 21598 and 6 for the division.

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 (1) of the dividend behind the 2 and repeat the process: 21 / 6

Step 2:
6 goes into 21 3 times with a remainder of 3.
Write down 3 as next digit of of the result. 
Result so far: 3
Subtract 18 from 21 to get 3.
Bring next digit (5) of the dividend behind the 3 and repeat the process: 35 / 6

Step 3:
6 goes into 35 5 times with a remainder of 5.
Write down 5 as next digit of of the result. 
Result so far: 35
Subtract 30 from 35 to get 5.
Bring next digit (9) of the dividend behind the 5 and repeat the process: 59 / 6

Step 4:
6 goes into 59 9 times with a remainder of 5.
Write down 9 as next digit of of the result. 
Result so far: 359
Subtract 54 from 59 to get 5.
Bring next digit (8) of the dividend behind the 5 and repeat the process: 58 / 6

Step 5:
6 goes into 58 9 times with a remainder of 4.
Write down 9 as next digit of of the result. 
Result so far: 3599
Subtract 54 from 58 to get 4.

The final result is 3599 with a remainder of 4.