20406285 ÷ 858 
Our goal is to divide 20406285 by 858.

On to step 1:
2 divided by 858 is 0 with a remainder of 2.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 2, we end up with 2.
Bring next digit (0) of the dividend behind the 2 and repeat the process: 20 / 858

Going ahead to step 2:
If we divide 20 by 858, we get 0 and a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 20 after subtracting 0 from 20.
Append the next digit (4) from the dividend to 20 and continue with: 204 / 858

Let's proceed to step 3:
858 can be fit into 204 0 times, resulting in a remainder of 204.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 204 and we're left with 204.
Grab the next digit (0) from the dividend, add it to 204, then carry on: 2040 / 858

Advancing to step 4:
If we divide 2040 by 858, we get 2 and a remainder of 324.
Put 2 as the next digit of the answer. 
Result so far: 2.0
Subtract 1716 from 2040 to get 324.
Bring next digit (6) of the dividend behind the 324 and repeat the process: 3246 / 858

Step 5:
858 goes into 3246 3 times with a remainder of 672.
Record the quotient 3 as the next digit in the result. 
Result so far: 23.0
Deduct 2574 from 3246 and we're left with 672.
Grab the next digit (2) from the dividend, add it to 672, then carry on: 6722 / 858

Moving on to step 6:
858 goes into 6722 7 times with a remainder of 716.
The next digit of our result is 7. 
Result so far: 237.0
If we take 6006 away from 6722, we end up with 716.
Fetch the next digit (8) from the dividend, attach it to 716 and continue: 7168 / 858

Moving on to step 7:
858 goes into 7168 8 times with a remainder of 304.
The next digit of our result is 8. 
Result so far: 2378.0
If we take 6864 away from 7168, we end up with 304.
Grab the next digit (5) from the dividend, add it to 304, then carry on: 3045 / 858

On to step 8:
3045 divided by 858 is 3 with a remainder of 471.
Record the quotient 3 as the next digit in the result. 
Result so far: 23783.0
The remainder is 471 after subtracting 2574 from 3045.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4710, and continue the process.

Advancing to step 9:
When dividing 4710 by 858, we get 5 with a remainder of 420.
Record the quotient 5 as the next digit in the result. 
Result so far: 23783.5
If we take 4290 away from 4710, we end up with 420.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4200, and continue the process.

Step 10:
858 goes into 4200 4 times with a remainder of 768.
Put 4 as the next digit of the answer. 
Result so far: 23783.54
Subtracting 3432 from 4200 leaves us with 768.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7680, and continue the process.

On to step 11:
If we divide 7680 by 858, we get 8 and a remainder of 816.
Write down 8 as next digit of the result. 
Result so far: 23783.548
If we take 6864 away from 7680, we end up with 816.
Since there are no more digits in the dividend, we add a zero to the remainder making it 8160, and continue the process.

Advancing to step 12:
858 can be fit into 8160 9 times, resulting in a remainder of 438.
Put 9 as the next digit of the answer. 
Result so far: 23783.5489
Subtracting 7722 from 8160 leaves us with 438.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4380, and continue the process.

On to step 13:
858 goes into 4380 5 times with a remainder of 90.
The next digit of our result is 5. 
Result so far: 23783.54895
If we take 4290 away from 4380, we end up with 90.
Since there are no more digits in the dividend, we add a zero to the remainder making it 900, and continue the process.

On to step 14:
When dividing 900 by 858, we get 1 with a remainder of 42.
Use 1 as the next digit of our solution. 
Result so far: 23783.548951
The remainder is 42 after subtracting 858 from 900.
Since there are no more digits in the dividend, we add a zero to the remainder making it 420, and continue the process.

Step 15:
When dividing 420 by 858, we get 0 with a remainder of 420.
Use 0 as the next digit of our solution. 
Result so far: 23783.548951
Deduct 0 from 420 and we're left with 420.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4200, and continue the process.

Moving on to step 16:
4200 divided by 858 is 4 with a remainder of 768.
Use 4 as the next digit of our solution. 
Result so far: 23783.54895104
If we subtract 3432 from 4200, we get 768.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7680, and continue the process.

The final result is 23783.54895104 with a remainder of 7.68e-07.