We look at the division of 8187401 by 639 
Our goal is to divide 8187401 by 639.

Advancing to step 1:
If we divide 8 by 639, we get 0 and a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Take the next digit (1) from the dividend and append it to 8, then repeat: 81 / 639

Let's proceed to step 2:
639 goes into 81 0 times with a remainder of 81.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 81, we end up with 81.
Bring next digit (8) of the dividend behind the 81 and repeat the process: 818 / 639

Moving on to step 3:
639 can be fit into 818 1 times, resulting in a remainder of 179.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
The remainder is 179 after subtracting 639 from 818.
Include the next digit (7) from the dividend after 179, then repeat: 1797 / 639

Advancing to step 4:
If we divide 1797 by 639, we get 2 and a remainder of 519.
Put 2 as the next digit of the answer. 
Result so far: 12.0
Subtract 1278 from 1797 to get 519.
Grab the next digit (4) from the dividend, add it to 519, then carry on: 5194 / 639

Step 5:
If we divide 5194 by 639, we get 8 and a remainder of 82.
Put 8 as the next digit of the answer. 
Result so far: 128.0
If we take 5112 away from 5194, we end up with 82.
Fetch the next digit (0) from the dividend, attach it to 82 and continue: 820 / 639

On to step 6:
820 divided by 639 is 1 with a remainder of 181.
Write down 1 as next digit of the result. 
Result so far: 1281.0
If we take 639 away from 820, we end up with 181.
Fetch the next digit (1) from the dividend, attach it to 181 and continue: 1811 / 639

Advancing to step 7:
639 can be fit into 1811 2 times, resulting in a remainder of 533.
Put 2 as the next digit of the answer. 
Result so far: 12812.0
Deduct 1278 from 1811 and we're left with 533.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5330, and continue the process.

Advancing to step 8:
The number 639 fits into 5330 8 times, leaving a remainder of 218.
Put 8 as the next digit of the answer. 
Result so far: 12812.8
Deduct 5112 from 5330 and we're left with 218.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2180, and continue the process.

Step 9:
639 can be fit into 2180 3 times, resulting in a remainder of 263.
Put 3 as the next digit of the answer. 
Result so far: 12812.83
If we take 1917 away from 2180, we end up with 263.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2630, and continue the process.

Advancing to step 10:
2630 divided by 639 is 4 with a remainder of 74.
The next digit of our result is 4. 
Result so far: 12812.834
The remainder is 74 after subtracting 2556 from 2630.
Since there are no more digits in the dividend, we add a zero to the remainder making it 740, and continue the process.

Advancing to step 11:
If we divide 740 by 639, we get 1 and a remainder of 101.
The number 1 becomes the next digit in our result. 
Result so far: 12812.8341
Deduct 639 from 740 and we're left with 101.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1010, and continue the process.

Going ahead to step 12:
1010 divided by 639 is 1 with a remainder of 371.
Put 1 as the next digit of the answer. 
Result so far: 12812.83411
If we take 639 away from 1010, we end up with 371.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3710, and continue the process.

In conclusion, the division gives 12812.83411 with a balance of 0.000371.