80638778 ÷ 21 
Our goal is to divide 80638778 by 21.

On to step 1:
If we divide 8 by 21, we get 0 and a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Grab the next digit (0) from the dividend, add it to 8, then carry on: 80 / 21

Let's proceed to step 2:
If we divide 80 by 21, we get 3 and a remainder of 17.
Use 3 as the next digit of our solution. 
Result so far: 3.0
Deduct 63 from 80 and we're left with 17.
Take the next digit (6) from the dividend and append it to 17, then repeat: 176 / 21

Let's proceed to step 3:
If we divide 176 by 21, we get 8 and a remainder of 8.
The next digit of our result is 8. 
Result so far: 38.0
Subtracting 168 from 176 leaves us with 8.
Append the next digit (3) from the dividend to 8 and continue with: 83 / 21

Let's proceed to step 4:
83 divided by 21 is 3 with a remainder of 20.
Write down 3 as next digit of the result. 
Result so far: 383.0
The remainder is 20 after subtracting 63 from 83.
Append the next digit (8) from the dividend to 20 and continue with: 208 / 21

Let's proceed to step 5:
The number 21 fits into 208 9 times, leaving a remainder of 19.
Use 9 as the next digit of our solution. 
Result so far: 3839.0
The remainder is 19 after subtracting 189 from 208.
Grab the next digit (7) from the dividend, add it to 19, then carry on: 197 / 21

Going ahead to step 6:
If we divide 197 by 21, we get 9 and a remainder of 8.
Use 9 as the next digit of our solution. 
Result so far: 38399.0
Subtracting 189 from 197 leaves us with 8.
Fetch the next digit (7) from the dividend, attach it to 8 and continue: 87 / 21

Advancing to step 7:
21 can be fit into 87 4 times, resulting in a remainder of 3.
The number 4 becomes the next digit in our result. 
Result so far: 383994.0
Subtracting 84 from 87 leaves us with 3.
Include the next digit (8) from the dividend after 3, then repeat: 38 / 21

Going ahead to step 8:
When dividing 38 by 21, we get 1 with a remainder of 17.
Use 1 as the next digit of our solution. 
Result so far: 3839941.0
If we take 21 away from 38, we end up with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Step 9:
21 can be fit into 170 8 times, resulting in a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 3839941.8
If we subtract 168 from 170, we get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

On to step 10:
If we divide 20 by 21, we get 0 and a remainder of 20.
Put 0 as the next digit of the answer. 
Result so far: 3839941.8
The remainder is 20 after subtracting 0 from 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Advancing to step 11:
When dividing 200 by 21, we get 9 with a remainder of 11.
Write down 9 as next digit of the result. 
Result so far: 3839941.809
Deduct 189 from 200 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 12:
When dividing 110 by 21, we get 5 with a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 3839941.8095
Subtracting 105 from 110 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Let's proceed to step 13:
21 can be fit into 50 2 times, resulting in a remainder of 8.
Use 2 as the next digit of our solution. 
Result so far: 3839941.80952
Subtracting 42 from 50 leaves us with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Going ahead to step 14:
80 divided by 21 is 3 with a remainder of 17.
The number 3 becomes the next digit in our result. 
Result so far: 3839941.809523
Subtract 63 from 80 to get 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Moving on to step 15:
If we divide 170 by 21, we get 8 and a remainder of 2.
The next digit of our result is 8. 
Result so far: 3839941.8095238
Subtract 168 from 170 to get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Moving on to step 16:
The number 21 fits into 20 0 times, leaving a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 3839941.8095238
Subtracting 0 from 20 leaves us with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

In conclusion, the division gives 3839941.8095238 with a balance of 2e-08.