We're dividing 25809515 by 820 
Our goal is to divide 25809515 by 820.

On to step 1:
The number 820 fits into 2 0 times, leaving a remainder of 2.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 2 and we're left with 2.
Grab the next digit (5) from the dividend, add it to 2, then carry on: 25 / 820

Advancing to step 2:
820 goes into 25 0 times with a remainder of 25.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 25 and we're left with 25.
Grab the next digit (8) from the dividend, add it to 25, then carry on: 258 / 820

Moving on to step 3:
If we divide 258 by 820, we get 0 and a remainder of 258.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 258 to get 258.
Include the next digit (0) from the dividend after 258, then repeat: 2580 / 820

On to step 4:
820 goes into 2580 3 times with a remainder of 120.
Put 3 as the next digit of the answer. 
Result so far: 3.0
Deduct 2460 from 2580 and we're left with 120.
Append the next digit (9) from the dividend to 120 and continue with: 1209 / 820

On to step 5:
820 can be fit into 1209 1 times, resulting in a remainder of 389.
Record the quotient 1 as the next digit in the result. 
Result so far: 31.0
The remainder is 389 after subtracting 820 from 1209.
Grab the next digit (5) from the dividend, add it to 389, then carry on: 3895 / 820

Moving on to step 6:
When dividing 3895 by 820, we get 4 with a remainder of 615.
Record the quotient 4 as the next digit in the result. 
Result so far: 314.0
The remainder is 615 after subtracting 3280 from 3895.
Include the next digit (1) from the dividend after 615, then repeat: 6151 / 820

Step 7:
When dividing 6151 by 820, we get 7 with a remainder of 411.
The next digit of our result is 7. 
Result so far: 3147.0
If we take 5740 away from 6151, we end up with 411.
Take the next digit (5) from the dividend and append it to 411, then repeat: 4115 / 820

Moving on to step 8:
If we divide 4115 by 820, we get 5 and a remainder of 15.
Use 5 as the next digit of our solution. 
Result so far: 31475.0
Subtract 4100 from 4115 to get 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Going ahead to step 9:
820 can be fit into 150 0 times, resulting in a remainder of 150.
Put 0 as the next digit of the answer. 
Result so far: 31475.0
If we take 0 away from 150, we end up 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.

On to step 10:
1500 divided by 820 is 1 with a remainder of 680.
The next digit of our result is 1. 
Result so far: 31475.01
If we subtract 820 from 1500, we get 680.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6800, and continue the process.

On to step 11:
The number 820 fits into 6800 8 times, leaving a remainder of 240.
Record the quotient 8 as the next digit in the result. 
Result so far: 31475.018
If we subtract 6560 from 6800, we get 240.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2400, and continue the process.

Step 12:
2400 divided by 820 is 2 with a remainder of 760.
The next digit of our result is 2. 
Result so far: 31475.0182
Subtract 1640 from 2400 to get 760.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7600, and continue the process.

Step 13:
When dividing 7600 by 820, we get 9 with a remainder of 220.
The number 9 becomes the next digit in our result. 
Result so far: 31475.01829
If we take 7380 away from 7600, we end up with 220.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2200, and continue the process.

Step 14:
The number 820 fits into 2200 2 times, leaving a remainder of 560.
The next digit of our result is 2. 
Result so far: 31475.018292
Subtract 1640 from 2200 to get 560.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5600, and continue the process.

Advancing to step 15:
5600 divided by 820 is 6 with a remainder of 680.
The next digit of our result is 6. 
Result so far: 31475.0182926
If we subtract 4920 from 5600, we get 680.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6800, and continue the process.

Step 16:
When dividing 6800 by 820, we get 8 with a remainder of 240.
Record the quotient 8 as the next digit in the result. 
Result so far: 31475.01829268
If we subtract 6560 from 6800, we get 240.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2400, and continue the process.

After the division, we end up with 31475.01829268 and a remainder of 2.4e-07.