21455059 ÷ 801 
Let's see how many times 801 fits into 21455059.

On to step 1:
801 goes into 2 0 times with a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 2 leaves us with 2.
Include the next digit (1) from the dividend after 2, then repeat: 21 / 801

Advancing to step 2:
21 divided by 801 is 0 with a remainder of 21.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 21, we get 21.
Include the next digit (4) from the dividend after 21, then repeat: 214 / 801

On to step 3:
When dividing 214 by 801, we get 0 with a remainder of 214.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 214, we end up with 214.
Fetch the next digit (5) from the dividend, attach it to 214 and continue: 2145 / 801

Advancing to step 4:
If we divide 2145 by 801, we get 2 and a remainder of 543.
The next digit of our result is 2. 
Result so far: 2.0
Deduct 1602 from 2145 and we're left with 543.
Fetch the next digit (5) from the dividend, attach it to 543 and continue: 5435 / 801

On to step 5:
801 can be fit into 5435 6 times, resulting in a remainder of 629.
Write down 6 as next digit of the result. 
Result so far: 26.0
If we take 4806 away from 5435, we end up with 629.
Take the next digit (0) from the dividend and append it to 629, then repeat: 6290 / 801

Going ahead to step 6:
The number 801 fits into 6290 7 times, leaving a remainder of 683.
Write down 7 as next digit of the result. 
Result so far: 267.0
Subtract 5607 from 6290 to get 683.
Grab the next digit (5) from the dividend, add it to 683, then carry on: 6835 / 801

Advancing to step 7:
When dividing 6835 by 801, we get 8 with a remainder of 427.
Write down 8 as next digit of the result. 
Result so far: 2678.0
If we take 6408 away from 6835, we end up with 427.
Grab the next digit (9) from the dividend, add it to 427, then carry on: 4279 / 801

On to step 8:
801 goes into 4279 5 times with a remainder of 274.
The number 5 becomes the next digit in our result. 
Result so far: 26785.0
The remainder is 274 after subtracting 4005 from 4279.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2740, and continue the process.

Going ahead to step 9:
If we divide 2740 by 801, we get 3 and a remainder of 337.
The number 3 becomes the next digit in our result. 
Result so far: 26785.3
Subtract 2403 from 2740 to get 337.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3370, and continue the process.

On to step 10:
The number 801 fits into 3370 4 times, leaving a remainder of 166.
Write down 4 as next digit of the result. 
Result so far: 26785.34
If we take 3204 away from 3370, we end up with 166.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1660, and continue the process.

Step 11:
The number 801 fits into 1660 2 times, leaving a remainder of 58.
Put 2 as the next digit of the answer. 
Result so far: 26785.342
Subtracting 1602 from 1660 leaves us with 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

Advancing to step 12:
801 can be fit into 580 0 times, resulting in a remainder of 580.
Use 0 as the next digit of our solution. 
Result so far: 26785.342
The remainder is 580 after subtracting 0 from 580.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5800, and continue the process.

Moving on to step 13:
When dividing 5800 by 801, we get 7 with a remainder of 193.
Use 7 as the next digit of our solution. 
Result so far: 26785.34207
Subtracting 5607 from 5800 leaves us with 193.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1930, and continue the process.

On to step 14:
1930 divided by 801 is 2 with a remainder of 328.
Write down 2 as next digit of the result. 
Result so far: 26785.342072
If we subtract 1602 from 1930, we get 328.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3280, and continue the process.

Advancing to step 15:
The number 801 fits into 3280 4 times, leaving a remainder of 76.
The next digit of our result is 4. 
Result so far: 26785.3420724
The remainder is 76 after subtracting 3204 from 3280.
Since there are no more digits in the dividend, we add a zero to the remainder making it 760, and continue the process.

Step 16:
801 goes into 760 0 times with a remainder of 760.
The number 0 becomes the next digit in our result. 
Result so far: 26785.3420724
If we subtract 0 from 760, we get 760.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7600, and continue the process.

After the division, we end up with 26785.3420724 and a remainder of 7.6e-07.