We divide 64257643 by 399
We want to figure out the number of times 64257643 can be divided by 399.

Moving on to step 1:
The number 399 fits into 6 0 times, leaving a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Take the next digit (4) from the dividend and append it to 6, then repeat: 64 / 399

Step 2:
399 goes into 64 0 times with a remainder of 64.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 64 leaves us with 64.
Take the next digit (2) from the dividend and append it to 64, then repeat: 642 / 399

Let's proceed to step 3:
When dividing 642 by 399, we get 1 with a remainder of 243.
The next digit of our result is 1. 
Result so far: 1.0
Subtract 399 from 642 to get 243.
Bring next digit (5) of the dividend behind the 243 and repeat the process: 2435 / 399

Let's proceed to step 4:
2435 divided by 399 is 6 with a remainder of 41.
The number 6 becomes the next digit in our result. 
Result so far: 16.0
The remainder is 41 after subtracting 2394 from 2435.
Fetch the next digit (7) from the dividend, attach it to 41 and continue: 417 / 399

Advancing to step 5:
399 goes into 417 1 times with a remainder of 18.
Record the quotient 1 as the next digit in the result. 
Result so far: 161.0
If we subtract 399 from 417, we get 18.
Bring next digit (6) of the dividend behind the 18 and repeat the process: 186 / 399

Step 6:
399 goes into 186 0 times with a remainder of 186.
Write down 0 as next digit of the result. 
Result so far: 1610.0
Subtract 0 from 186 to get 186.
Take the next digit (4) from the dividend and append it to 186, then repeat: 1864 / 399

Advancing to step 7:
1864 divided by 399 is 4 with a remainder of 268.
Use 4 as the next digit of our solution. 
Result so far: 16104.0
The remainder is 268 after subtracting 1596 from 1864.
Grab the next digit (3) from the dividend, add it to 268, then carry on: 2683 / 399

Moving on to step 8:
399 can be fit into 2683 6 times, resulting in a remainder of 289.
The number 6 becomes the next digit in our result. 
Result so far: 161046.0
If we subtract 2394 from 2683, we get 289.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2890, and continue the process.

Advancing to step 9:
399 can be fit into 2890 7 times, resulting in a remainder of 97.
Put 7 as the next digit of the answer. 
Result so far: 161046.7
If we subtract 2793 from 2890, we get 97.
Since there are no more digits in the dividend, we add a zero to the remainder making it 970, and continue the process.

On to step 10:
The number 399 fits into 970 2 times, leaving a remainder of 172.
The number 2 becomes the next digit in our result. 
Result so far: 161046.72
The remainder is 172 after subtracting 798 from 970.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1720, and continue the process.

On to step 11:
The number 399 fits into 1720 4 times, leaving a remainder of 124.
The number 4 becomes the next digit in our result. 
Result so far: 161046.724
The remainder is 124 after subtracting 1596 from 1720.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1240, and continue the process.

Step 12:
399 can be fit into 1240 3 times, resulting in a remainder of 43.
Use 3 as the next digit of our solution. 
Result so far: 161046.7243
The remainder is 43 after subtracting 1197 from 1240.
Since there are no more digits in the dividend, we add a zero to the remainder making it 430, and continue the process.

Let's proceed to step 13:
The number 399 fits into 430 1 times, leaving a remainder of 31.
Write down 1 as next digit of the result. 
Result so far: 161046.72431
The remainder is 31 after subtracting 399 from 430.
Since there are no more digits in the dividend, we add a zero to the remainder making it 310, and continue the process.

Moving on to step 14:
When dividing 310 by 399, we get 0 with a remainder of 310.
Use 0 as the next digit of our solution. 
Result so far: 161046.72431
Subtracting 0 from 310 leaves us with 310.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3100, and continue the process.

Going ahead to step 15:
If we divide 3100 by 399, we get 7 and a remainder of 307.
Put 7 as the next digit of the answer. 
Result so far: 161046.7243107
The remainder is 307 after subtracting 2793 from 3100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3070, and continue the process.

Advancing to step 16:
When dividing 3070 by 399, we get 7 with a remainder of 277.
The next digit of our result is 7. 
Result so far: 161046.72431077
If we subtract 2793 from 3070, we get 277.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2770, and continue the process.

The final outcome is 161046.72431077, with a leftover of 2.77e-07.