17420089 ÷ 858 
We want to figure out the number of times 17420089 can be divided by 858.

Moving on to step 1:
The number 858 fits into 1 0 times, leaving a remainder of 1.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 1 and we're left with 1.
Append the next digit (7) from the dividend to 1 and continue with: 17 / 858

Step 2:
When dividing 17 by 858, we get 0 with a remainder of 17.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 17, we get 17.
Append the next digit (4) from the dividend to 17 and continue with: 174 / 858

Let's proceed to step 3:
858 can be fit into 174 0 times, resulting in a remainder of 174.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 174, we get 174.
Grab the next digit (2) from the dividend, add it to 174, then carry on: 1742 / 858

Step 4:
1742 divided by 858 is 2 with a remainder of 26.
Use 2 as the next digit of our solution. 
Result so far: 2.0
If we take 1716 away from 1742, we end up with 26.
Take the next digit (0) from the dividend and append it to 26, then repeat: 260 / 858

On to step 5:
260 divided by 858 is 0 with a remainder of 260.
Record the quotient 0 as the next digit in the result. 
Result so far: 20.0
If we take 0 away from 260, we end up with 260.
Fetch the next digit (0) from the dividend, attach it to 260 and continue: 2600 / 858

Advancing to step 6:
If we divide 2600 by 858, we get 3 and a remainder of 26.
The next digit of our result is 3. 
Result so far: 203.0
Subtracting 2574 from 2600 leaves us with 26.
Grab the next digit (8) from the dividend, add it to 26, then carry on: 268 / 858

On to step 7:
858 can be fit into 268 0 times, resulting in a remainder of 268.
The number 0 becomes the next digit in our result. 
Result so far: 2030.0
The remainder is 268 after subtracting 0 from 268.
Take the next digit (9) from the dividend and append it to 268, then repeat: 2689 / 858

Step 8:
858 can be fit into 2689 3 times, resulting in a remainder of 115.
Record the quotient 3 as the next digit in the result. 
Result so far: 20303.0
Subtract 2574 from 2689 to get 115.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1150, and continue the process.

Let's proceed to step 9:
1150 divided by 858 is 1 with a remainder of 292.
Use 1 as the next digit of our solution. 
Result so far: 20303.1
Subtract 858 from 1150 to get 292.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2920, and continue the process.

Let's proceed to step 10:
The number 858 fits into 2920 3 times, leaving a remainder of 346.
The next digit of our result is 3. 
Result so far: 20303.13
If we subtract 2574 from 2920, we get 346.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3460, and continue the process.

Let's proceed to step 11:
The number 858 fits into 3460 4 times, leaving a remainder of 28.
Write down 4 as next digit of the result. 
Result so far: 20303.134
Subtracting 3432 from 3460 leaves us with 28.
Since there are no more digits in the dividend, we add a zero to the remainder making it 280, and continue the process.

Advancing to step 12:
858 goes into 280 0 times with a remainder of 280.
Use 0 as the next digit of our solution. 
Result so far: 20303.134
Subtracting 0 from 280 leaves us with 280.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2800, and continue the process.

Going ahead to step 13:
2800 divided by 858 is 3 with a remainder of 226.
Record the quotient 3 as the next digit in the result. 
Result so far: 20303.13403
If we take 2574 away from 2800, we end up with 226.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2260, and continue the process.

Going ahead to step 14:
858 can be fit into 2260 2 times, resulting in a remainder of 544.
The number 2 becomes the next digit in our result. 
Result so far: 20303.134032
The remainder is 544 after subtracting 1716 from 2260.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5440, and continue the process.

Advancing to step 15:
When dividing 5440 by 858, we get 6 with a remainder of 292.
Write down 6 as next digit of the result. 
Result so far: 20303.1340326
If we take 5148 away from 5440, we end up with 292.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2920, and continue the process.

Let's proceed to step 16:
858 can be fit into 2920 3 times, resulting in a remainder of 346.
Put 3 as the next digit of the answer. 
Result so far: 20303.13403263
The remainder is 346 after subtracting 2574 from 2920.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3460, and continue the process.

The final outcome is 20303.13403263, with a leftover of 3.46e-07.