We're dividing 86840183 by 621 
We want to figure out the number of times 86840183 can be divided by 621.

Going ahead to step 1:
If we divide 8 by 621, we get 0 and a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Append the next digit (6) from the dividend to 8 and continue with: 86 / 621

Going ahead to step 2:
621 can be fit into 86 0 times, resulting in a remainder of 86.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 86, we get 86.
Grab the next digit (8) from the dividend, add it to 86, then carry on: 868 / 621

Step 3:
If we divide 868 by 621, we get 1 and a remainder of 247.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
If we subtract 621 from 868, we get 247.
Grab the next digit (4) from the dividend, add it to 247, then carry on: 2474 / 621

On to step 4:
621 can be fit into 2474 3 times, resulting in a remainder of 611.
Use 3 as the next digit of our solution. 
Result so far: 13.0
Deduct 1863 from 2474 and we're left with 611.
Bring next digit (0) of the dividend behind the 611 and repeat the process: 6110 / 621

Moving on to step 5:
If we divide 6110 by 621, we get 9 and a remainder of 521.
Use 9 as the next digit of our solution. 
Result so far: 139.0
Subtract 5589 from 6110 to get 521.
Bring next digit (1) of the dividend behind the 521 and repeat the process: 5211 / 621

Going ahead to step 6:
621 can be fit into 5211 8 times, resulting in a remainder of 243.
Write down 8 as next digit of the result. 
Result so far: 1398.0
The remainder is 243 after subtracting 4968 from 5211.
Take the next digit (8) from the dividend and append it to 243, then repeat: 2438 / 621

Advancing to step 7:
621 goes into 2438 3 times with a remainder of 575.
The number 3 becomes the next digit in our result. 
Result so far: 13983.0
Subtracting 1863 from 2438 leaves us with 575.
Take the next digit (3) from the dividend and append it to 575, then repeat: 5753 / 621

Step 8:
621 can be fit into 5753 9 times, resulting in a remainder of 164.
The number 9 becomes the next digit in our result. 
Result so far: 139839.0
The remainder is 164 after subtracting 5589 from 5753.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1640, and continue the process.

Advancing to step 9:
621 goes into 1640 2 times with a remainder of 398.
Record the quotient 2 as the next digit in the result. 
Result so far: 139839.2
Deduct 1242 from 1640 and we're left with 398.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3980, and continue the process.

Let's proceed to step 10:
If we divide 3980 by 621, we get 6 and a remainder of 254.
Record the quotient 6 as the next digit in the result. 
Result so far: 139839.26
Deduct 3726 from 3980 and we're left with 254.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2540, and continue the process.

Advancing to step 11:
621 can be fit into 2540 4 times, resulting in a remainder of 56.
Write down 4 as next digit of the result. 
Result so far: 139839.264
If we take 2484 away from 2540, we end up with 56.
Since there are no more digits in the dividend, we add a zero to the remainder making it 560, and continue the process.

Advancing to step 12:
If we divide 560 by 621, we get 0 and a remainder of 560.
Put 0 as the next digit of the answer. 
Result so far: 139839.264
Subtract 0 from 560 to get 560.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5600, and continue the process.

Advancing to step 13:
5600 divided by 621 is 9 with a remainder of 11.
The next digit of our result is 9. 
Result so far: 139839.26409
Deduct 5589 from 5600 and we're left with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Advancing to step 14:
The number 621 fits into 110 0 times, leaving a remainder of 110.
The next digit of our result is 0. 
Result so far: 139839.26409
Deduct 0 from 110 and we're left with 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1100, and continue the process.

Advancing to step 15:
621 goes into 1100 1 times with a remainder of 479.
Use 1 as the next digit of our solution. 
Result so far: 139839.2640901
Subtracting 621 from 1100 leaves us with 479.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4790, and continue the process.

On to step 16:
621 goes into 4790 7 times with a remainder of 443.
Put 7 as the next digit of the answer. 
Result so far: 139839.26409017
If we take 4347 away from 4790, we end up with 443.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4430, and continue the process.

The final outcome is 139839.26409017, with a leftover of 4.43e-07.