We divide 63521645 by 15
We're looking to find how many times 15 goes into 63521645.

Moving on to step 1:
When dividing 6 by 15, we get 0 with a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Take the next digit (3) from the dividend and append it to 6, then repeat: 63 / 15

Let's proceed to step 2:
15 can be fit into 63 4 times, resulting in a remainder of 3.
Write down 4 as next digit of the result. 
Result so far: 4.0
If we subtract 60 from 63, we get 3.
Take the next digit (5) from the dividend and append it to 3, then repeat: 35 / 15

Going ahead to step 3:
15 can be fit into 35 2 times, resulting in a remainder of 5.
Record the quotient 2 as the next digit in the result. 
Result so far: 42.0
Subtract 30 from 35 to get 5.
Bring next digit (2) of the dividend behind the 5 and repeat the process: 52 / 15

Advancing to step 4:
15 can be fit into 52 3 times, resulting in a remainder of 7.
Record the quotient 3 as the next digit in the result. 
Result so far: 423.0
Subtract 45 from 52 to get 7.
Grab the next digit (1) from the dividend, add it to 7, then carry on: 71 / 15

On to step 5:
15 can be fit into 71 4 times, resulting in a remainder of 11.
Put 4 as the next digit of the answer. 
Result so far: 4234.0
If we subtract 60 from 71, we get 11.
Fetch the next digit (6) from the dividend, attach it to 11 and continue: 116 / 15

On to step 6:
If we divide 116 by 15, we get 7 and a remainder of 11.
Use 7 as the next digit of our solution. 
Result so far: 42347.0
The remainder is 11 after subtracting 105 from 116.
Grab the next digit (4) from the dividend, add it to 11, then carry on: 114 / 15

Step 7:
114 divided by 15 is 7 with a remainder of 9.
The next digit of our result is 7. 
Result so far: 423477.0
Subtracting 105 from 114 leaves us with 9.
Grab the next digit (5) from the dividend, add it to 9, then carry on: 95 / 15

Let's proceed to step 8:
The number 15 fits into 95 6 times, leaving a remainder of 5.
The next digit of our result is 6. 
Result so far: 4234776.0
Subtract 90 from 95 to get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Advancing to step 9:
15 goes into 50 3 times with a remainder of 5.
Record the quotient 3 as the next digit in the result. 
Result so far: 4234776.3
Subtracting 45 from 50 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Step 10:
15 goes into 50 3 times with a remainder of 5.
Record the quotient 3 as the next digit in the result. 
Result so far: 4234776.33
Subtracting 45 from 50 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

In conclusion, the division gives 4234776.33 with a balance of 0.005.