78620563 ÷ 639 
We want to divide 78620563 by 639.

Advancing to step 1:
When dividing 7 by 639, we get 0 with a remainder of 7.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 7 leaves us with 7.
Append the next digit (8) from the dividend to 7 and continue with: 78 / 639

Let's proceed to step 2:
639 goes into 78 0 times with a remainder of 78.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 78, we get 78.
Grab the next digit (6) from the dividend, add it to 78, then carry on: 786 / 639

Moving on to step 3:
The number 639 fits into 786 1 times, leaving a remainder of 147.
Use 1 as the next digit of our solution. 
Result so far: 1.0
Subtracting 639 from 786 leaves us with 147.
Append the next digit (2) from the dividend to 147 and continue with: 1472 / 639

Going ahead to step 4:
1472 divided by 639 is 2 with a remainder of 194.
The number 2 becomes the next digit in our result. 
Result so far: 12.0
If we take 1278 away from 1472, we end up with 194.
Take the next digit (0) from the dividend and append it to 194, then repeat: 1940 / 639

On to step 5:
The number 639 fits into 1940 3 times, leaving a remainder of 23.
Record the quotient 3 as the next digit in the result. 
Result so far: 123.0
If we take 1917 away from 1940, we end up with 23.
Grab the next digit (5) from the dividend, add it to 23, then carry on: 235 / 639

Step 6:
If we divide 235 by 639, we get 0 and a remainder of 235.
Use 0 as the next digit of our solution. 
Result so far: 1230.0
If we subtract 0 from 235, we get 235.
Append the next digit (6) from the dividend to 235 and continue with: 2356 / 639

Let's proceed to step 7:
639 goes into 2356 3 times with a remainder of 439.
Use 3 as the next digit of our solution. 
Result so far: 12303.0
The remainder is 439 after subtracting 1917 from 2356.
Grab the next digit (3) from the dividend, add it to 439, then carry on: 4393 / 639

Advancing to step 8:
The number 639 fits into 4393 6 times, leaving a remainder of 559.
Record the quotient 6 as the next digit in the result. 
Result so far: 123036.0
Subtract 3834 from 4393 to get 559.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5590, and continue the process.

Advancing to step 9:
639 goes into 5590 8 times with a remainder of 478.
The next digit of our result is 8. 
Result so far: 123036.8
If we subtract 5112 from 5590, we get 478.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4780, and continue the process.

Advancing to step 10:
The number 639 fits into 4780 7 times, leaving a remainder of 307.
Put 7 as the next digit of the answer. 
Result so far: 123036.87
Deduct 4473 from 4780 and we're left with 307.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3070, and continue the process.

Let's proceed to step 11:
The number 639 fits into 3070 4 times, leaving a remainder of 514.
Use 4 as the next digit of our solution. 
Result so far: 123036.874
The remainder is 514 after subtracting 2556 from 3070.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5140, and continue the process.

Going ahead to step 12:
639 goes into 5140 8 times with a remainder of 28.
The next digit of our result is 8. 
Result so far: 123036.8748
If we take 5112 away from 5140, we end up with 28.
Since there are no more digits in the dividend, we add a zero to the remainder making it 280, and continue the process.

Moving on to step 13:
When dividing 280 by 639, we get 0 with a remainder of 280.
The next digit of our result is 0. 
Result so far: 123036.8748
Subtracting 0 from 280 leaves us with 280.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2800, and continue the process.

Step 14:
639 can be fit into 2800 4 times, resulting in a remainder of 244.
Record the quotient 4 as the next digit in the result. 
Result so far: 123036.874804
If we subtract 2556 from 2800, we get 244.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2440, and continue the process.

Advancing to step 15:
The number 639 fits into 2440 3 times, leaving a remainder of 523.
Put 3 as the next digit of the answer. 
Result so far: 123036.8748043
Deduct 1917 from 2440 and we're left with 523.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5230, and continue the process.

Let's proceed to step 16:
The number 639 fits into 5230 8 times, leaving a remainder of 118.
Put 8 as the next digit of the answer. 
Result so far: 123036.87480438
If we subtract 5112 from 5230, we get 118.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1180, and continue the process.

The final outcome is 123036.87480438, with a leftover of 1.18e-07.