39941518 ÷ 405 
Our goal is to divide 39941518 by 405.

Step 1:
3 divided by 405 is 0 with a remainder of 3.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 3 to get 3.
Fetch the next digit (9) from the dividend, attach it to 3 and continue: 39 / 405

On to step 2:
405 goes into 39 0 times with a remainder of 39.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 39 after subtracting 0 from 39.
Grab the next digit (9) from the dividend, add it to 39, then carry on: 399 / 405

Step 3:
If we divide 399 by 405, we get 0 and a remainder of 399.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 399 and we're left with 399.
Fetch the next digit (4) from the dividend, attach it to 399 and continue: 3994 / 405

Let's proceed to step 4:
If we divide 3994 by 405, we get 9 and a remainder of 349.
Write down 9 as next digit of the result. 
Result so far: 9.0
The remainder is 349 after subtracting 3645 from 3994.
Bring next digit (1) of the dividend behind the 349 and repeat the process: 3491 / 405

Going ahead to step 5:
When dividing 3491 by 405, we get 8 with a remainder of 251.
The next digit of our result is 8. 
Result so far: 98.0
If we subtract 3240 from 3491, we get 251.
Append the next digit (5) from the dividend to 251 and continue with: 2515 / 405

Let's proceed to step 6:
When dividing 2515 by 405, we get 6 with a remainder of 85.
The next digit of our result is 6. 
Result so far: 986.0
Deduct 2430 from 2515 and we're left with 85.
Include the next digit (1) from the dividend after 85, then repeat: 851 / 405

Going ahead to step 7:
If we divide 851 by 405, we get 2 and a remainder of 41.
Record the quotient 2 as the next digit in the result. 
Result so far: 9862.0
Deduct 810 from 851 and we're left with 41.
Bring next digit (8) of the dividend behind the 41 and repeat the process: 418 / 405

Moving on to step 8:
418 divided by 405 is 1 with a remainder of 13.
The next digit of our result is 1. 
Result so far: 98621.0
If we take 405 away from 418, we end up 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.

Let's proceed to step 9:
The number 405 fits into 130 0 times, leaving a remainder of 130.
Put 0 as the next digit of the answer. 
Result so far: 98621.0
Subtract 0 from 130 to get 130.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1300, and continue the process.

On to step 10:
The number 405 fits into 1300 3 times, leaving a remainder of 85.
The next digit of our result is 3. 
Result so far: 98621.03
Deduct 1215 from 1300 and we're left with 85.
Since there are no more digits in the dividend, we add a zero to the remainder making it 850, and continue the process.

On to step 11:
405 goes into 850 2 times with a remainder of 40.
The number 2 becomes the next digit in our result. 
Result so far: 98621.032
Subtract 810 from 850 to get 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Going ahead to step 12:
The number 405 fits into 400 0 times, leaving a remainder of 400.
Use 0 as the next digit of our solution. 
Result so far: 98621.032
Subtract 0 from 400 to get 400.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4000, and continue the process.

Step 13:
4000 divided by 405 is 9 with a remainder of 355.
Use 9 as the next digit of our solution. 
Result so far: 98621.03209
Subtract 3645 from 4000 to get 355.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3550, and continue the process.

Moving on to step 14:
The number 405 fits into 3550 8 times, leaving a remainder of 310.
Record the quotient 8 as the next digit in the result. 
Result so far: 98621.032098
The remainder is 310 after subtracting 3240 from 3550.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3100, and continue the process.

Step 15:
If we divide 3100 by 405, we get 7 and a remainder of 265.
The number 7 becomes the next digit in our result. 
Result so far: 98621.0320987
Subtracting 2835 from 3100 leaves us with 265.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2650, and continue the process.

Going ahead to step 16:
If we divide 2650 by 405, we get 6 and a remainder of 220.
Put 6 as the next digit of the answer. 
Result so far: 98621.03209876
If we take 2430 away from 2650, we end up with 220.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2200, and continue the process.

The final outcome is 98621.03209876, with a leftover of 2.2e-07.