21541190 ÷ 398 
We want to figure out the number of times 21541190 can be divided by 398.

Going ahead to step 1:
2 divided by 398 is 0 with a remainder of 2.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Append the next digit (1) from the dividend to 2 and continue with: 21 / 398

Going ahead to step 2:
When dividing 21 by 398, we get 0 with a remainder of 21.
Use 0 as the next digit of our solution. 
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 / 398

Going ahead to step 3:
When dividing 215 by 398, we get 0 with a remainder of 215.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 215, we get 215.
Grab the next digit (4) from the dividend, add it to 215, then carry on: 2154 / 398

Going ahead to step 4:
If we divide 2154 by 398, we get 5 and a remainder of 164.
Put 5 as the next digit of the answer. 
Result so far: 5.0
The remainder is 164 after subtracting 1990 from 2154.
Bring next digit (1) of the dividend behind the 164 and repeat the process: 1641 / 398

Moving on to step 5:
1641 divided by 398 is 4 with a remainder of 49.
Use 4 as the next digit of our solution. 
Result so far: 54.0
Deduct 1592 from 1641 and we're left with 49.
Grab the next digit (1) from the dividend, add it to 49, then carry on: 491 / 398

Step 6:
When dividing 491 by 398, we get 1 with a remainder of 93.
The number 1 becomes the next digit in our result. 
Result so far: 541.0
Deduct 398 from 491 and we're left with 93.
Grab the next digit (9) from the dividend, add it to 93, then carry on: 939 / 398

Going ahead to step 7:
398 goes into 939 2 times with a remainder of 143.
Record the quotient 2 as the next digit in the result. 
Result so far: 5412.0
Subtracting 796 from 939 leaves us with 143.
Grab the next digit (0) from the dividend, add it to 143, then carry on: 1430 / 398

Going ahead to step 8:
The number 398 fits into 1430 3 times, leaving a remainder of 236.
Put 3 as the next digit of the answer. 
Result so far: 54123.0
If we take 1194 away from 1430, we end up with 236.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2360, and continue the process.

Let's proceed to step 9:
The number 398 fits into 2360 5 times, leaving a remainder of 370.
Put 5 as the next digit of the answer. 
Result so far: 54123.5
If we take 1990 away from 2360, we end up with 370.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3700, and continue the process.

Let's proceed to step 10:
The number 398 fits into 3700 9 times, leaving a remainder of 118.
Record the quotient 9 as the next digit in the result. 
Result so far: 54123.59
The remainder is 118 after subtracting 3582 from 3700.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1180, and continue the process.

Let's proceed to step 11:
398 goes into 1180 2 times with a remainder of 384.
Write down 2 as next digit of the result. 
Result so far: 54123.592
The remainder is 384 after subtracting 796 from 1180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3840, and continue the process.

On to step 12:
When dividing 3840 by 398, we get 9 with a remainder of 258.
Use 9 as the next digit of our solution. 
Result so far: 54123.5929
Subtract 3582 from 3840 to get 258.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2580, and continue the process.

Moving on to step 13:
When dividing 2580 by 398, we get 6 with a remainder of 192.
Use 6 as the next digit of our solution. 
Result so far: 54123.59296
The remainder is 192 after subtracting 2388 from 2580.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1920, and continue the process.

Moving on to step 14:
When dividing 1920 by 398, we get 4 with a remainder of 328.
Use 4 as the next digit of our solution. 
Result so far: 54123.592964
Deduct 1592 from 1920 and we're left with 328.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3280, and continue the process.

On to step 15:
The number 398 fits into 3280 8 times, leaving a remainder of 96.
The next digit of our result is 8. 
Result so far: 54123.5929648
If we subtract 3184 from 3280, we get 96.
Since there are no more digits in the dividend, we add a zero to the remainder making it 960, and continue the process.

Going ahead to step 16:
398 can be fit into 960 2 times, resulting in a remainder of 164.
Use 2 as the next digit of our solution. 
Result so far: 54123.59296482
The remainder is 164 after subtracting 796 from 960.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1640, and continue the process.

The final result is 54123.59296482 with a remainder of 1.64e-07.