12789612 ÷ 210 
Let's see how many times 210 fits into 12789612.

Moving on to step 1:
The number 210 fits into 1 0 times, leaving a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 1 to get 1.
Append the next digit (2) from the dividend to 1 and continue with: 12 / 210

Moving on to step 2:
12 divided by 210 is 0 with a remainder of 12.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 12 leaves us with 12.
Append the next digit (7) from the dividend to 12 and continue with: 127 / 210

On to step 3:
When dividing 127 by 210, we get 0 with a remainder of 127.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 127 to get 127.
Bring next digit (8) of the dividend behind the 127 and repeat the process: 1278 / 210

Step 4:
The number 210 fits into 1278 6 times, leaving a remainder of 18.
Use 6 as the next digit of our solution. 
Result so far: 6.0
Subtract 1260 from 1278 to get 18.
Include the next digit (9) from the dividend after 18, then repeat: 189 / 210

Advancing to step 5:
189 divided by 210 is 0 with a remainder of 189.
Record the quotient 0 as the next digit in the result. 
Result so far: 60.0
Subtracting 0 from 189 leaves us with 189.
Bring next digit (6) of the dividend behind the 189 and repeat the process: 1896 / 210

Advancing to step 6:
If we divide 1896 by 210, we get 9 and a remainder of 6.
Record the quotient 9 as the next digit in the result. 
Result so far: 609.0
If we subtract 1890 from 1896, we get 6.
Include the next digit (1) from the dividend after 6, then repeat: 61 / 210

Going ahead to step 7:
210 can be fit into 61 0 times, resulting in a remainder of 61.
Write down 0 as next digit of the result. 
Result so far: 6090.0
Deduct 0 from 61 and we're left with 61.
Take the next digit (2) from the dividend and append it to 61, then repeat: 612 / 210

Advancing to step 8:
When dividing 612 by 210, we get 2 with a remainder of 192.
Put 2 as the next digit of the answer. 
Result so far: 60902.0
Deduct 420 from 612 and we're left with 192.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1920, and continue the process.

Moving on to step 9:
210 can be fit into 1920 9 times, resulting in a remainder of 30.
Write down 9 as next digit of the result. 
Result so far: 60902.9
If we take 1890 away from 1920, we end up with 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Let's proceed to step 10:
210 can be fit into 300 1 times, resulting in a remainder of 90.
Put 1 as the next digit of the answer. 
Result so far: 60902.91
Subtracting 210 from 300 leaves us with 90.
Since there are no more digits in the dividend, we add a zero to the remainder making it 900, and continue the process.

Advancing to step 11:
900 divided by 210 is 4 with a remainder of 60.
Record the quotient 4 as the next digit in the result. 
Result so far: 60902.914
Deduct 840 from 900 and we're left with 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 600, and continue the process.

Advancing to step 12:
When dividing 600 by 210, we get 2 with a remainder of 180.
The number 2 becomes the next digit in our result. 
Result so far: 60902.9142
If we take 420 away from 600, we end up with 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1800, and continue the process.

Advancing to step 13:
The number 210 fits into 1800 8 times, leaving a remainder of 120.
Use 8 as the next digit of our solution. 
Result so far: 60902.91428
Deduct 1680 from 1800 and we're left with 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1200, and continue the process.

Advancing to step 14:
The number 210 fits into 1200 5 times, leaving a remainder of 150.
Use 5 as the next digit of our solution. 
Result so far: 60902.914285
Deduct 1050 from 1200 and we're left with 150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1500, and continue the process.

Moving on to step 15:
When dividing 1500 by 210, we get 7 with a remainder of 30.
Write down 7 as next digit of the result. 
Result so far: 60902.9142857
The remainder is 30 after subtracting 1470 from 1500.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Advancing to step 16:
300 divided by 210 is 1 with a remainder of 90.
Put 1 as the next digit of the answer. 
Result so far: 60902.91428571
If we subtract 210 from 300, we get 90.
Since there are no more digits in the dividend, we add a zero to the remainder making it 900, and continue the process.

The final outcome is 60902.91428571, with a leftover of 9e-08.