Let's divide 21358106 by 603
We want to figure out the number of times 21358106 can be divided by 603.

Going ahead to step 1:
603 goes into 2 0 times with a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 2 after subtracting 0 from 2.
Include the next digit (1) from the dividend after 2, then repeat: 21 / 603

On to step 2:
If we divide 21 by 603, we get 0 and a remainder of 21.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 21 and we're left with 21.
Include the next digit (3) from the dividend after 21, then repeat: 213 / 603

Advancing to step 3:
The number 603 fits into 213 0 times, leaving a remainder of 213.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 213, we end up with 213.
Bring next digit (5) of the dividend behind the 213 and repeat the process: 2135 / 603

Step 4:
When dividing 2135 by 603, we get 3 with a remainder of 326.
Use 3 as the next digit of our solution. 
Result so far: 3.0
Deduct 1809 from 2135 and we're left with 326.
Grab the next digit (8) from the dividend, add it to 326, then carry on: 3268 / 603

Let's proceed to step 5:
603 goes into 3268 5 times with a remainder of 253.
Put 5 as the next digit of the answer. 
Result so far: 35.0
Subtracting 3015 from 3268 leaves us with 253.
Take the next digit (1) from the dividend and append it to 253, then repeat: 2531 / 603

Step 6:
The number 603 fits into 2531 4 times, leaving a remainder of 119.
Use 4 as the next digit of our solution. 
Result so far: 354.0
If we subtract 2412 from 2531, we get 119.
Append the next digit (0) from the dividend to 119 and continue with: 1190 / 603

On to step 7:
603 can be fit into 1190 1 times, resulting in a remainder of 587.
Write down 1 as next digit of the result. 
Result so far: 3541.0
Subtracting 603 from 1190 leaves us with 587.
Include the next digit (6) from the dividend after 587, then repeat: 5876 / 603

Moving on to step 8:
If we divide 5876 by 603, we get 9 and a remainder of 449.
Write down 9 as next digit of the result. 
Result so far: 35419.0
If we subtract 5427 from 5876, we get 449.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4490, and continue the process.

Step 9:
4490 divided by 603 is 7 with a remainder of 269.
Put 7 as the next digit of the answer. 
Result so far: 35419.7
Subtract 4221 from 4490 to get 269.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2690, and continue the process.

Advancing to step 10:
603 can be fit into 2690 4 times, resulting in a remainder of 278.
Record the quotient 4 as the next digit in the result. 
Result so far: 35419.74
The remainder is 278 after subtracting 2412 from 2690.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2780, and continue the process.

Let's proceed to step 11:
2780 divided by 603 is 4 with a remainder of 368.
Use 4 as the next digit of our solution. 
Result so far: 35419.744
If we subtract 2412 from 2780, we get 368.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3680, and continue the process.

The final outcome is 35419.744, with a leftover of 0.0368.