We look at the division of 876421 by 1 
We want to divide 876421 by 1.

On to step 1:
1 can be fit into 8 8 times, resulting in a remainder of 0.
The next digit of our result is 8. 
Result so far: 8.0
Deduct 8 from 8 and we're left with 0.
Grab the next digit (7) from the dividend, add it to 0, then carry on: 7 / 1

On to step 2:
7 divided by 1 is 7 with a remainder of 0.
Record the quotient 7 as the next digit in the result. 
Result so far: 87.0
Subtracting 7 from 7 leaves us with 0.
Fetch the next digit (6) from the dividend, attach it to 0 and continue: 6 / 1

Step 3:
1 can be fit into 6 6 times, resulting in a remainder of 0.
The number 6 becomes the next digit in our result. 
Result so far: 876.0
The remainder is 0 after subtracting 6 from 6.
Take the next digit (4) from the dividend and append it to 0, then repeat: 4 / 1

Let's proceed to step 4:
If we divide 4 by 1, we get 4 and a remainder of 0.
Write down 4 as next digit of the result. 
Result so far: 8764.0
Deduct 4 from 4 and we're left with 0.
Grab the next digit (2) from the dividend, add it to 0, then carry on: 2 / 1

Going ahead to step 5:
When dividing 2 by 1, we get 2 with a remainder of 0.
The number 2 becomes the next digit in our result. 
Result so far: 87642.0
If we take 2 away from 2, we end up with 0.
Grab the next digit (1) from the dividend, add it to 0, then carry on: 1 / 1

Let's proceed to step 6:
1 goes into 1 1 times with a remainder of 0.
The number 1 becomes the next digit in our result. 
Result so far: 876421.0
Subtract 1 from 1 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 7:
If we divide 0 by 1, we get 0 and a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 876421.0
Subtracting 0 from 0 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 8:
The number 1 fits into 0 0 times, leaving a remainder of 0.
The next digit of our result is 0. 
Result so far: 876421.0
Subtract 0 from 0 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final result is 876421.0 with a remainder of 0.0.