71571523 ÷ 21 
Let's see how many times 21 fits into 71571523.

On to step 1:
21 can be fit into 7 0 times, resulting in a remainder of 7.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 7, we end up with 7.
Include the next digit (1) from the dividend after 7, then repeat: 71 / 21

On to step 2:
When dividing 71 by 21, we get 3 with a remainder of 8.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
If we subtract 63 from 71, we get 8.
Include the next digit (5) from the dividend after 8, then repeat: 85 / 21

Going ahead to step 3:
21 can be fit into 85 4 times, resulting in a remainder of 1.
The number 4 becomes the next digit in our result. 
Result so far: 34.0
Deduct 84 from 85 and we're left with 1.
Fetch the next digit (7) from the dividend, attach it to 1 and continue: 17 / 21

Advancing to step 4:
21 goes into 17 0 times with a remainder of 17.
Use 0 as the next digit of our solution. 
Result so far: 340.0
If we take 0 away from 17, we end up with 17.
Fetch the next digit (1) from the dividend, attach it to 17 and continue: 171 / 21

Let's proceed to step 5:
The number 21 fits into 171 8 times, leaving a remainder of 3.
The next digit of our result is 8. 
Result so far: 3408.0
Deduct 168 from 171 and we're left with 3.
Include the next digit (5) from the dividend after 3, then repeat: 35 / 21

Going ahead to step 6:
21 can be fit into 35 1 times, resulting in a remainder of 14.
Put 1 as the next digit of the answer. 
Result so far: 34081.0
The remainder is 14 after subtracting 21 from 35.
Take the next digit (2) from the dividend and append it to 14, then repeat: 142 / 21

Advancing to step 7:
21 goes into 142 6 times with a remainder of 16.
Write down 6 as next digit of the result. 
Result so far: 340816.0
The remainder is 16 after subtracting 126 from 142.
Include the next digit (3) from the dividend after 16, then repeat: 163 / 21

On to step 8:
The number 21 fits into 163 7 times, leaving a remainder of 16.
The next digit of our result is 7. 
Result so far: 3408167.0
Subtract 147 from 163 to get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Going ahead to step 9:
21 can be fit into 160 7 times, resulting in a remainder of 13.
The number 7 becomes the next digit in our result. 
Result so far: 3408167.7
Subtracting 147 from 160 leaves us with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Going ahead to step 10:
When dividing 130 by 21, we get 6 with a remainder of 4.
The next digit of our result is 6. 
Result so far: 3408167.76
If we subtract 126 from 130, we get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Going ahead to step 11:
21 goes into 40 1 times with a remainder of 19.
Use 1 as the next digit of our solution. 
Result so far: 3408167.761
Deduct 21 from 40 and we're left with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Let's proceed to step 12:
When dividing 190 by 21, we get 9 with a remainder of 1.
The next digit of our result is 9. 
Result so far: 3408167.7619
Subtracting 189 from 190 leaves us with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Going ahead to step 13:
The number 21 fits into 10 0 times, leaving a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 3408167.7619
Deduct 0 from 10 and we're left with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Let's proceed to step 14:
If we divide 100 by 21, we get 4 and a remainder of 16.
Put 4 as the next digit of the answer. 
Result so far: 3408167.761904
If we take 84 away from 100, we end up with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

On to step 15:
21 can be fit into 160 7 times, resulting in a remainder of 13.
The next digit of our result is 7. 
Result so far: 3408167.7619047
Subtracting 147 from 160 leaves us with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Step 16:
130 divided by 21 is 6 with a remainder of 4.
The number 6 becomes the next digit in our result. 
Result so far: 3408167.76190476
If we subtract 126 from 130, we get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

The final result is 3408167.76190476 with a remainder of 4e-09.