764643 divided by 21 
We're looking to find how many times 21 goes into 764643.

Moving on to step 1:
7 divided by 21 is 0 with a remainder of 7.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 7 to get 7.
Append the next digit (6) from the dividend to 7 and continue with: 76 / 21

On to step 2:
The number 21 fits into 76 3 times, leaving a remainder of 13.
Write down 3 as next digit of the result. 
Result so far: 3.0
If we subtract 63 from 76, we get 13.
Take the next digit (4) from the dividend and append it to 13, then repeat: 134 / 21

Moving on to step 3:
When dividing 134 by 21, we get 6 with a remainder of 8.
Put 6 as the next digit of the answer. 
Result so far: 36.0
Deduct 126 from 134 and we're left with 8.
Grab the next digit (6) from the dividend, add it to 8, then carry on: 86 / 21

On to step 4:
86 divided by 21 is 4 with a remainder of 2.
The next digit of our result is 4. 
Result so far: 364.0
Subtract 84 from 86 to get 2.
Append the next digit (4) from the dividend to 2 and continue with: 24 / 21

Advancing to step 5:
21 goes into 24 1 times with a remainder of 3.
Use 1 as the next digit of our solution. 
Result so far: 3641.0
Deduct 21 from 24 and we're left with 3.
Bring next digit (3) of the dividend behind the 3 and repeat the process: 33 / 21

Moving on to step 6:
When dividing 33 by 21, we get 1 with a remainder of 12.
Put 1 as the next digit of the answer. 
Result so far: 36411.0
If we take 21 away from 33, we end up with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Step 7:
The number 21 fits into 120 5 times, leaving a remainder of 15.
Write down 5 as next digit of the result. 
Result so far: 36411.5
The remainder is 15 after subtracting 105 from 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

On to step 8:
21 can be fit into 150 7 times, resulting in a remainder of 3.
Record the quotient 7 as the next digit in the result. 
Result so far: 36411.57
Subtract 147 from 150 to get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

On to step 9:
30 divided by 21 is 1 with a remainder of 9.
Use 1 as the next digit of our solution. 
Result so far: 36411.571
If we take 21 away from 30, we end up with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Moving on to step 10:
The number 21 fits into 90 4 times, leaving a remainder of 6.
The next digit of our result is 4. 
Result so far: 36411.5714
Deduct 84 from 90 and we're left with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Step 11:
60 divided by 21 is 2 with a remainder of 18.
The number 2 becomes the next digit in our result. 
Result so far: 36411.57142
If we subtract 42 from 60, we get 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Advancing to step 12:
180 divided by 21 is 8 with a remainder of 12.
Record the quotient 8 as the next digit in the result. 
Result so far: 36411.571428
If we subtract 168 from 180, 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.

On to step 13:
The number 21 fits into 120 5 times, leaving a remainder of 15.
The next digit of our result is 5. 
Result so far: 36411.5714285
If we subtract 105 from 120, we get 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Moving on to step 14:
150 divided by 21 is 7 with a remainder of 3.
Record the quotient 7 as the next digit in the result. 
Result so far: 36411.57142857
Deduct 147 from 150 and we're left with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

The quotient of the division is 36411.57142857, and the remainder is 3e-09.