We look at the division of 221370 by 12 
We want to figure out the number of times 221370 can be divided by 12.

Step 1:
2 divided by 12 is 0 with a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Take the next digit (2) from the dividend and append it to 2, then repeat: 22 / 12

Step 2:
When dividing 22 by 12, we get 1 with a remainder of 10.
The next digit of our result is 1. 
Result so far: 1.0
Subtracting 12 from 22 leaves us with 10.
Grab the next digit (1) from the dividend, add it to 10, then carry on: 101 / 12

Advancing to step 3:
The number 12 fits into 101 8 times, leaving a remainder of 5.
Write down 8 as next digit of the result. 
Result so far: 18.0
Subtract 96 from 101 to get 5.
Take the next digit (3) from the dividend and append it to 5, then repeat: 53 / 12

Moving on to step 4:
12 can be fit into 53 4 times, resulting in a remainder of 5.
Put 4 as the next digit of the answer. 
Result so far: 184.0
Subtract 48 from 53 to get 5.
Append the next digit (7) from the dividend to 5 and continue with: 57 / 12

Going ahead to step 5:
57 divided by 12 is 4 with a remainder of 9.
Put 4 as the next digit of the answer. 
Result so far: 1844.0
Subtracting 48 from 57 leaves us with 9.
Bring next digit (0) of the dividend behind the 9 and repeat the process: 90 / 12

Let's proceed to step 6:
12 can be fit into 90 7 times, resulting in a remainder of 6.
The number 7 becomes the next digit in our result. 
Result so far: 18447.0
If we subtract 84 from 90, we get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

On to step 7:
12 can be fit into 60 5 times, resulting in a remainder of 0.
Write down 5 as next digit of the result. 
Result so far: 18447.5
If we subtract 60 from 60, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 8:
12 goes into 0 0 times with a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 18447.5
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

On to step 9:
When dividing 0 by 12, we get 0 with a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 18447.5
Subtract 0 from 0 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

In conclusion, the division gives 18447.5 with a balance of 0.0.