640391 ÷ 34 
We're looking to find how many times 34 goes into 640391.

Moving on to step 1:
34 goes into 6 0 times with a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Grab the next digit (4) from the dividend, add it to 6, then carry on: 64 / 34

Step 2:
The number 34 fits into 64 1 times, leaving a remainder of 30.
The next digit of our result is 1. 
Result so far: 1.0
Deduct 34 from 64 and we're left with 30.
Fetch the next digit (0) from the dividend, attach it to 30 and continue: 300 / 34

Going ahead to step 3:
The number 34 fits into 300 8 times, leaving a remainder of 28.
Write down 8 as next digit of the result. 
Result so far: 18.0
If we take 272 away from 300, we end up with 28.
Include the next digit (3) from the dividend after 28, then repeat: 283 / 34

Let's proceed to step 4:
The number 34 fits into 283 8 times, leaving a remainder of 11.
Put 8 as the next digit of the answer. 
Result so far: 188.0
If we subtract 272 from 283, we get 11.
Include the next digit (9) from the dividend after 11, then repeat: 119 / 34

Advancing to step 5:
The number 34 fits into 119 3 times, leaving a remainder of 17.
Write down 3 as next digit of the result. 
Result so far: 1883.0
Subtract 102 from 119 to get 17.
Bring next digit (1) of the dividend behind the 17 and repeat the process: 171 / 34

Moving on to step 6:
171 divided by 34 is 5 with a remainder of 1.
The next digit of our result is 5. 
Result so far: 18835.0
The remainder is 1 after subtracting 170 from 171.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Going ahead to step 7:
When dividing 10 by 34, we get 0 with a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 18835.0
If we subtract 0 from 10, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Advancing to step 8:
If we divide 100 by 34, we get 2 and a remainder of 32.
The number 2 becomes the next digit in our result. 
Result so far: 18835.02
The remainder is 32 after subtracting 68 from 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Let's proceed to step 9:
34 can be fit into 320 9 times, resulting in a remainder of 14.
The number 9 becomes the next digit in our result. 
Result so far: 18835.029
Subtracting 306 from 320 leaves us with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Advancing to step 10:
34 goes into 140 4 times with a remainder of 4.
Put 4 as the next digit of the answer. 
Result so far: 18835.0294
Subtracting 136 from 140 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 11:
If we divide 40 by 34, we get 1 and a remainder of 6.
Write down 1 as next digit of the result. 
Result so far: 18835.02941
Deduct 34 from 40 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.

On to step 12:
34 can be fit into 60 1 times, resulting in a remainder of 26.
The number 1 becomes the next digit in our result. 
Result so far: 18835.029411
If we take 34 away from 60, we end up with 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

The final outcome is 18835.029411, with a leftover of 2.6e-06.