21100712 ÷ 45 
We're looking to find how many times 45 goes into 21100712.

On to step 1:
The number 45 fits into 2 0 times, leaving a remainder of 2.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 2 after subtracting 0 from 2.
Grab the next digit (1) from the dividend, add it to 2, then carry on: 21 / 45

Let's proceed to step 2:
45 goes into 21 0 times with a remainder of 21.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 21 to get 21.
Grab the next digit (1) from the dividend, add it to 21, then carry on: 211 / 45

Step 3:
211 divided by 45 is 4 with a remainder of 31.
Write down 4 as next digit of the result. 
Result so far: 4.0
The remainder is 31 after subtracting 180 from 211.
Take the next digit (0) from the dividend and append it to 31, then repeat: 310 / 45

Going ahead to step 4:
When dividing 310 by 45, we get 6 with a remainder of 40.
Write down 6 as next digit of the result. 
Result so far: 46.0
The remainder is 40 after subtracting 270 from 310.
Bring next digit (0) of the dividend behind the 40 and repeat the process: 400 / 45

Let's proceed to step 5:
45 goes into 400 8 times with a remainder of 40.
The next digit of our result is 8. 
Result so far: 468.0
Subtracting 360 from 400 leaves us with 40.
Take the next digit (7) from the dividend and append it to 40, then repeat: 407 / 45

Let's proceed to step 6:
When dividing 407 by 45, we get 9 with a remainder of 2.
The next digit of our result is 9. 
Result so far: 4689.0
The remainder is 2 after subtracting 405 from 407.
Take the next digit (1) from the dividend and append it to 2, then repeat: 21 / 45

Step 7:
45 goes into 21 0 times with a remainder of 21.
The number 0 becomes the next digit in our result. 
Result so far: 46890.0
If we subtract 0 from 21, we get 21.
Include the next digit (2) from the dividend after 21, then repeat: 212 / 45

Moving on to step 8:
If we divide 212 by 45, we get 4 and a remainder of 32.
Put 4 as the next digit of the answer. 
Result so far: 468904.0
Subtracting 180 from 212 leaves us with 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Step 9:
45 can be fit into 320 7 times, resulting in a remainder of 5.
The number 7 becomes the next digit in our result. 
Result so far: 468904.7
Deduct 315 from 320 and we're left 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.

Let's proceed to step 10:
The number 45 fits into 50 1 times, leaving a remainder of 5.
Use 1 as the next digit of our solution. 
Result so far: 468904.71
If we take 45 away from 50, we end up 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.

On to step 11:
The number 45 fits into 50 1 times, leaving a remainder of 5.
The next digit of our result is 1. 
Result so far: 468904.711
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.

The final result is 468904.711 with a remainder of 0.0005.