84399111 ÷ 144 
We want to figure out the number of times 84399111 can be divided by 144.

Step 1:
8 divided by 144 is 0 with a remainder of 8.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Bring next digit (4) of the dividend behind the 8 and repeat the process: 84 / 144

On to step 2:
144 can be fit into 84 0 times, resulting in a remainder of 84.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 84 after subtracting 0 from 84.
Append the next digit (3) from the dividend to 84 and continue with: 843 / 144

Going ahead to step 3:
When dividing 843 by 144, we get 5 with a remainder of 123.
The next digit of our result is 5. 
Result so far: 5.0
Deduct 720 from 843 and we're left with 123.
Append the next digit (9) from the dividend to 123 and continue with: 1239 / 144

Going ahead to step 4:
The number 144 fits into 1239 8 times, leaving a remainder of 87.
The number 8 becomes the next digit in our result. 
Result so far: 58.0
Subtract 1152 from 1239 to get 87.
Take the next digit (9) from the dividend and append it to 87, then repeat: 879 / 144

Step 5:
When dividing 879 by 144, we get 6 with a remainder of 15.
Write down 6 as next digit of the result. 
Result so far: 586.0
Subtract 864 from 879 to get 15.
Append the next digit (1) from the dividend to 15 and continue with: 151 / 144

On to step 6:
144 goes into 151 1 times with a remainder of 7.
Use 1 as the next digit of our solution. 
Result so far: 5861.0
Subtract 144 from 151 to get 7.
Fetch the next digit (1) from the dividend, attach it to 7 and continue: 71 / 144

Step 7:
144 goes into 71 0 times with a remainder of 71.
The number 0 becomes the next digit in our result. 
Result so far: 58610.0
Subtracting 0 from 71 leaves us with 71.
Grab the next digit (1) from the dividend, add it to 71, then carry on: 711 / 144

Moving on to step 8:
144 goes into 711 4 times with a remainder of 135.
The number 4 becomes the next digit in our result. 
Result so far: 586104.0
If we take 576 away from 711, we end up with 135.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1350, and continue the process.

Moving on to step 9:
If we divide 1350 by 144, we get 9 and a remainder of 54.
Record the quotient 9 as the next digit in the result. 
Result so far: 586104.9
If we take 1296 away from 1350, we end up with 54.
Since there are no more digits in the dividend, we add a zero to the remainder making it 540, and continue the process.

On to step 10:
144 goes into 540 3 times with a remainder of 108.
Use 3 as the next digit of our solution. 
Result so far: 586104.93
If we subtract 432 from 540, we get 108.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1080, and continue the process.

Step 11:
1080 divided by 144 is 7 with a remainder of 72.
Put 7 as the next digit of the answer. 
Result so far: 586104.937
Subtract 1008 from 1080 to 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.

Let's proceed to step 12:
When dividing 720 by 144, we get 5 with a remainder of 0.
Record the quotient 5 as the next digit in the result. 
Result so far: 586104.9375
Subtracting 720 from 720 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 13:
When dividing 0 by 144, we get 0 with a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 586104.9375
If we take 0 away from 0, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Advancing to step 14:
The number 144 fits into 0 0 times, leaving a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 586104.9375
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

After the division, we end up with 586104.9375 and a remainder of 0.0.