We're dividing 12521907 by 828 
We're looking to find how many times 828 goes into 12521907.

On to step 1:
The number 828 fits into 1 0 times, leaving a remainder of 1.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 1 to get 1.
Bring next digit (2) of the dividend behind the 1 and repeat the process: 12 / 828

Going ahead to step 2:
The number 828 fits into 12 0 times, leaving a remainder of 12.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 12 to get 12.
Include the next digit (5) from the dividend after 12, then repeat: 125 / 828

Going ahead to step 3:
If we divide 125 by 828, we get 0 and a remainder of 125.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 125, we end up with 125.
Include the next digit (2) from the dividend after 125, then repeat: 1252 / 828

Going ahead to step 4:
The number 828 fits into 1252 1 times, leaving a remainder of 424.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
If we subtract 828 from 1252, we get 424.
Append the next digit (1) from the dividend to 424 and continue with: 4241 / 828

On to step 5:
The number 828 fits into 4241 5 times, leaving a remainder of 101.
The number 5 becomes the next digit in our result. 
Result so far: 15.0
If we subtract 4140 from 4241, we get 101.
Take the next digit (9) from the dividend and append it to 101, then repeat: 1019 / 828

Step 6:
The number 828 fits into 1019 1 times, leaving a remainder of 191.
Use 1 as the next digit of our solution. 
Result so far: 151.0
Deduct 828 from 1019 and we're left with 191.
Bring next digit (0) of the dividend behind the 191 and repeat the process: 1910 / 828

Let's proceed to step 7:
1910 divided by 828 is 2 with a remainder of 254.
The next digit of our result is 2. 
Result so far: 1512.0
Subtract 1656 from 1910 to get 254.
Grab the next digit (7) from the dividend, add it to 254, then carry on: 2547 / 828

On to step 8:
828 can be fit into 2547 3 times, resulting in a remainder of 63.
Put 3 as the next digit of the answer. 
Result so far: 15123.0
Subtracting 2484 from 2547 leaves us with 63.
Since there are no more digits in the dividend, we add a zero to the remainder making it 630, and continue the process.

Step 9:
If we divide 630 by 828, we get 0 and a remainder of 630.
The number 0 becomes the next digit in our result. 
Result so far: 15123.0
If we subtract 0 from 630, we get 630.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6300, and continue the process.

Advancing to step 10:
828 goes into 6300 7 times with a remainder of 504.
The number 7 becomes the next digit in our result. 
Result so far: 15123.07
Subtracting 5796 from 6300 leaves us with 504.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5040, and continue the process.

Moving on to step 11:
5040 divided by 828 is 6 with a remainder of 72.
The number 6 becomes the next digit in our result. 
Result so far: 15123.076
If we subtract 4968 from 5040, we get 72.
Since there are no more digits in the dividend, we add a zero to the remainder making it 720, and continue the process.

On to step 12:
720 divided by 828 is 0 with a remainder of 720.
Put 0 as the next digit of the answer. 
Result so far: 15123.076
If we take 0 away from 720, we end up with 720.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7200, and continue the process.

Step 13:
The number 828 fits into 7200 8 times, leaving a remainder of 576.
Put 8 as the next digit of the answer. 
Result so far: 15123.07608
Subtracting 6624 from 7200 leaves us with 576.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5760, and continue the process.

On to step 14:
828 can be fit into 5760 6 times, resulting in a remainder of 792.
Write down 6 as next digit of the result. 
Result so far: 15123.076086
Subtract 4968 from 5760 to get 792.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7920, and continue the process.

Going ahead to step 15:
The number 828 fits into 7920 9 times, leaving a remainder of 468.
Put 9 as the next digit of the answer. 
Result so far: 15123.0760869
If we subtract 7452 from 7920, we get 468.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4680, and continue the process.

Moving on to step 16:
828 goes into 4680 5 times with a remainder of 540.
Use 5 as the next digit of our solution. 
Result so far: 15123.07608695
Subtract 4140 from 4680 to get 540.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5400, and continue the process.

The final result is 15123.07608695 with a remainder of 5.4e-07.