84121 ÷ 7 = 12017 R2
Let's divide 84121 by 7.

Step 1:
7 goes into 8 1 times with a remainder of 1.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 7 from 8 to get 1.
Bring next digit (4) of the dividend behind the 1 and repeat the process: 14 / 7

Step 2:
7 goes into 14 2 times with a remainder of 0.
Write down 2 as next digit of of the result. 
Result so far: 12
Subtract 14 from 14 to get 0.
Bring next digit (1) of the dividend behind the 0 and repeat the process: 1 / 7

Step 3:
7 goes into 1 0 times with a remainder of 1.
Write down 0 as next digit of of the result. 
Result so far: 120
Subtract 0 from 1 to get 1.
Bring next digit (2) of the dividend behind the 1 and repeat the process: 12 / 7

Step 4:
7 goes into 12 1 times with a remainder of 5.
Write down 1 as next digit of of the result. 
Result so far: 1201
Subtract 7 from 12 to get 5.
Bring next digit (1) of the dividend behind the 5 and repeat the process: 51 / 7

Step 5:
7 goes into 51 7 times with a remainder of 2.
Write down 7 as next digit of of the result. 
Result so far: 12017
Subtract 49 from 51 to get 2.

The final result is 12017 with a remainder of 2.