364590 ÷ 21 
Our goal is to divide 364590 by 21.

Advancing to step 1:
21 can be fit into 3 0 times, resulting in a remainder of 3.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 3, we get 3.
Fetch the next digit (6) from the dividend, attach it to 3 and continue: 36 / 21

Let's proceed to step 2:
The number 21 fits into 36 1 times, leaving a remainder of 15.
The next digit of our result is 1. 
Result so far: 1.0
Subtract 21 from 36 to get 15.
Grab the next digit (4) from the dividend, add it to 15, then carry on: 154 / 21

On to step 3:
21 goes into 154 7 times with a remainder of 7.
Write down 7 as next digit of the result. 
Result so far: 17.0
Deduct 147 from 154 and we're left with 7.
Take the next digit (5) from the dividend and append it to 7, then repeat: 75 / 21

Let's proceed to step 4:
If we divide 75 by 21, we get 3 and a remainder of 12.
Write down 3 as next digit of the result. 
Result so far: 173.0
The remainder is 12 after subtracting 63 from 75.
Take the next digit (9) from the dividend and append it to 12, then repeat: 129 / 21

Moving on to step 5:
The number 21 fits into 129 6 times, leaving a remainder of 3.
Put 6 as the next digit of the answer. 
Result so far: 1736.0
Subtracting 126 from 129 leaves us with 3.
Bring next digit (0) of the dividend behind the 3 and repeat the process: 30 / 21

Let's proceed to step 6:
If we divide 30 by 21, we get 1 and a remainder of 9.
The next digit of our result is 1. 
Result so far: 17361.0
The remainder is 9 after subtracting 21 from 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Step 7:
21 goes into 90 4 times with a remainder of 6.
The number 4 becomes the next digit in our result. 
Result so far: 17361.4
Deduct 84 from 90 and we're left with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Step 8:
The number 21 fits into 60 2 times, leaving a remainder of 18.
Write down 2 as next digit of the result. 
Result so far: 17361.42
The remainder is 18 after subtracting 42 from 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Going ahead to step 9:
180 divided by 21 is 8 with a remainder of 12.
Write down 8 as next digit of the result. 
Result so far: 17361.428
The remainder is 12 after subtracting 168 from 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

On to step 10:
21 goes into 120 5 times with a remainder of 15.
Record the quotient 5 as the next digit in the result. 
Result so far: 17361.4285
If we take 105 away from 120, we end up with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Let's proceed to step 11:
150 divided by 21 is 7 with a remainder of 3.
Write down 7 as next digit of the result. 
Result so far: 17361.42857
The remainder is 3 after subtracting 147 from 150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Step 12:
If we divide 30 by 21, we get 1 and a remainder of 9.
Write down 1 as next digit of the result. 
Result so far: 17361.428571
Subtract 21 from 30 to get 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Step 13:
21 can be fit into 90 4 times, resulting in a remainder of 6.
The next digit of our result is 4. 
Result so far: 17361.4285714
The remainder is 6 after subtracting 84 from 90.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Going ahead to step 14:
When dividing 60 by 21, we get 2 with a remainder of 18.
The number 2 becomes the next digit in our result. 
Result so far: 17361.42857142
If we take 42 away from 60, we end up with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Our division results in 17361.42857142 with a remaining 1.8e-08.