Let's divide 21571537 by 578
We're looking to find how many times 578 goes into 21571537.

Advancing to step 1:
When dividing 2 by 578, we get 0 with a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 2, we end up with 2.
Fetch the next digit (1) from the dividend, attach it to 2 and continue: 21 / 578

Let's proceed to step 2:
The number 578 fits into 21 0 times, leaving a remainder of 21.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 21, we end up with 21.
Take the next digit (5) from the dividend and append it to 21, then repeat: 215 / 578

Step 3:
If we divide 215 by 578, we get 0 and a remainder of 215.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 215 leaves us with 215.
Take the next digit (7) from the dividend and append it to 215, then repeat: 2157 / 578

Step 4:
When dividing 2157 by 578, we get 3 with a remainder of 423.
Write down 3 as next digit of the result. 
Result so far: 3.0
Deduct 1734 from 2157 and we're left with 423.
Append the next digit (1) from the dividend to 423 and continue with: 4231 / 578

Going ahead to step 5:
578 goes into 4231 7 times with a remainder of 185.
Write down 7 as next digit of the result. 
Result so far: 37.0
Subtracting 4046 from 4231 leaves us with 185.
Grab the next digit (5) from the dividend, add it to 185, then carry on: 1855 / 578

Going ahead to step 6:
The number 578 fits into 1855 3 times, leaving a remainder of 121.
The number 3 becomes the next digit in our result. 
Result so far: 373.0
Subtract 1734 from 1855 to get 121.
Bring next digit (3) of the dividend behind the 121 and repeat the process: 1213 / 578

On to step 7:
1213 divided by 578 is 2 with a remainder of 57.
Put 2 as the next digit of the answer. 
Result so far: 3732.0
If we take 1156 away from 1213, we end up with 57.
Bring next digit (7) of the dividend behind the 57 and repeat the process: 577 / 578

Step 8:
The number 578 fits into 577 0 times, leaving a remainder of 577.
The next digit of our result is 0. 
Result so far: 37320.0
Subtracting 0 from 577 leaves us with 577.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5770, and continue the process.

Step 9:
When dividing 5770 by 578, we get 9 with a remainder of 568.
The number 9 becomes the next digit in our result. 
Result so far: 37320.9
Deduct 5202 from 5770 and we're left with 568.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5680, and continue the process.

Going ahead to step 10:
When dividing 5680 by 578, we get 9 with a remainder of 478.
The number 9 becomes the next digit in our result. 
Result so far: 37320.99
Deduct 5202 from 5680 and we're left with 478.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4780, and continue the process.

After the division, we end up with 37320.99 and a remainder of 0.478.