21491216 divided by 391 
Our goal is to divide 21491216 by 391.

Advancing to step 1:
If we divide 2 by 391, we get 0 and a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 2, we end up with 2.
Grab the next digit (1) from the dividend, add it to 2, then carry on: 21 / 391

On to step 2:
391 can be fit into 21 0 times, resulting in a remainder of 21.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 21, we end up with 21.
Take the next digit (4) from the dividend and append it to 21, then repeat: 214 / 391

Going ahead to step 3:
391 goes into 214 0 times with a remainder of 214.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 214, we end up with 214.
Include the next digit (9) from the dividend after 214, then repeat: 2149 / 391

Moving on to step 4:
If we divide 2149 by 391, we get 5 and a remainder of 194.
Put 5 as the next digit of the answer. 
Result so far: 5.0
If we take 1955 away from 2149, we end up with 194.
Take the next digit (1) from the dividend and append it to 194, then repeat: 1941 / 391

Advancing to step 5:
1941 divided by 391 is 4 with a remainder of 377.
The number 4 becomes the next digit in our result. 
Result so far: 54.0
Subtracting 1564 from 1941 leaves us with 377.
Grab the next digit (2) from the dividend, add it to 377, then carry on: 3772 / 391

Let's proceed to step 6:
3772 divided by 391 is 9 with a remainder of 253.
Write down 9 as next digit of the result. 
Result so far: 549.0
Subtract 3519 from 3772 to get 253.
Fetch the next digit (1) from the dividend, attach it to 253 and continue: 2531 / 391

Moving on to step 7:
The number 391 fits into 2531 6 times, leaving a remainder of 185.
The next digit of our result is 6. 
Result so far: 5496.0
Subtracting 2346 from 2531 leaves us with 185.
Append the next digit (6) from the dividend to 185 and continue with: 1856 / 391

Going ahead to step 8:
391 can be fit into 1856 4 times, resulting in a remainder of 292.
The number 4 becomes the next digit in our result. 
Result so far: 54964.0
If we take 1564 away from 1856, we end up with 292.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2920, and continue the process.

Moving on to step 9:
When dividing 2920 by 391, we get 7 with a remainder of 183.
The next digit of our result is 7. 
Result so far: 54964.7
If we subtract 2737 from 2920, we get 183.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1830, and continue the process.

Advancing to step 10:
The number 391 fits into 1830 4 times, leaving a remainder of 266.
Write down 4 as next digit of the result. 
Result so far: 54964.74
Deduct 1564 from 1830 and we're left with 266.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2660, and continue the process.

On to step 11:
391 can be fit into 2660 6 times, resulting in a remainder of 314.
Write down 6 as next digit of the result. 
Result so far: 54964.746
The remainder is 314 after subtracting 2346 from 2660.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3140, and continue the process.

Step 12:
When dividing 3140 by 391, we get 8 with a remainder of 12.
Use 8 as the next digit of our solution. 
Result so far: 54964.7468
If we subtract 3128 from 3140, we get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Moving on to step 13:
391 goes into 120 0 times with a remainder of 120.
Use 0 as the next digit of our solution. 
Result so far: 54964.7468
The remainder is 120 after subtracting 0 from 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1200, and continue the process.

Step 14:
1200 divided by 391 is 3 with a remainder of 27.
Write down 3 as next digit of the result. 
Result so far: 54964.746803
The remainder is 27 after subtracting 1173 from 1200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 270, and continue the process.

Let's proceed to step 15:
When dividing 270 by 391, we get 0 with a remainder of 270.
Record the quotient 0 as the next digit in the result. 
Result so far: 54964.746803
Subtract 0 from 270 to get 270.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2700, and continue the process.

Moving on to step 16:
2700 divided by 391 is 6 with a remainder of 354.
Use 6 as the next digit of our solution. 
Result so far: 54964.74680306
Subtracting 2346 from 2700 leaves us with 354.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3540, and continue the process.

The quotient of the division is 54964.74680306, and the remainder is 3.54e-07.