23453010 ÷ 399 
Let's see how many times 399 fits into 23453010.

Step 1:
399 can be fit into 2 0 times, resulting in a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 2 after subtracting 0 from 2.
Fetch the next digit (3) from the dividend, attach it to 2 and continue: 23 / 399

Step 2:
399 goes into 23 0 times with a remainder of 23.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 23 leaves us with 23.
Take the next digit (4) from the dividend and append it to 23, then repeat: 234 / 399

Going ahead to step 3:
234 divided by 399 is 0 with a remainder of 234.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 234, we end up with 234.
Take the next digit (5) from the dividend and append it to 234, then repeat: 2345 / 399

On to step 4:
When dividing 2345 by 399, we get 5 with a remainder of 350.
The next digit of our result is 5. 
Result so far: 5.0
Deduct 1995 from 2345 and we're left with 350.
Fetch the next digit (3) from the dividend, attach it to 350 and continue: 3503 / 399

Step 5:
If we divide 3503 by 399, we get 8 and a remainder of 311.
Record the quotient 8 as the next digit in the result. 
Result so far: 58.0
If we subtract 3192 from 3503, we get 311.
Append the next digit (0) from the dividend to 311 and continue with: 3110 / 399

Going ahead to step 6:
399 goes into 3110 7 times with a remainder of 317.
Use 7 as the next digit of our solution. 
Result so far: 587.0
If we take 2793 away from 3110, we end up with 317.
Append the next digit (1) from the dividend to 317 and continue with: 3171 / 399

Moving on to step 7:
If we divide 3171 by 399, we get 7 and a remainder of 378.
The number 7 becomes the next digit in our result. 
Result so far: 5877.0
If we subtract 2793 from 3171, we get 378.
Grab the next digit (0) from the dividend, add it to 378, then carry on: 3780 / 399

Step 8:
The number 399 fits into 3780 9 times, leaving a remainder of 189.
Record the quotient 9 as the next digit in the result. 
Result so far: 58779.0
If we subtract 3591 from 3780, we get 189.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1890, and continue the process.

Let's proceed to step 9:
399 can be fit into 1890 4 times, resulting in a remainder of 294.
Put 4 as the next digit of the answer. 
Result so far: 58779.4
The remainder is 294 after subtracting 1596 from 1890.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2940, and continue the process.

On to step 10:
When dividing 2940 by 399, we get 7 with a remainder of 147.
Write down 7 as next digit of the result. 
Result so far: 58779.47
If we take 2793 away from 2940, we end up with 147.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1470, and continue the process.

Moving on to step 11:
The number 399 fits into 1470 3 times, leaving a remainder of 273.
Put 3 as the next digit of the answer. 
Result so far: 58779.473
If we take 1197 away from 1470, we end up with 273.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2730, and continue the process.

Moving on to step 12:
If we divide 2730 by 399, we get 6 and a remainder of 336.
The number 6 becomes the next digit in our result. 
Result so far: 58779.4736
If we subtract 2394 from 2730, we get 336.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3360, and continue the process.

Let's proceed to step 13:
The number 399 fits into 3360 8 times, leaving a remainder of 168.
Record the quotient 8 as the next digit in the result. 
Result so far: 58779.47368
Subtract 3192 from 3360 to get 168.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1680, and continue the process.

Let's proceed to step 14:
399 goes into 1680 4 times with a remainder of 84.
Use 4 as the next digit of our solution. 
Result so far: 58779.473684
If we subtract 1596 from 1680, we get 84.
Since there are no more digits in the dividend, we add a zero to the remainder making it 840, and continue the process.

Step 15:
When dividing 840 by 399, we get 2 with a remainder of 42.
The number 2 becomes the next digit in our result. 
Result so far: 58779.4736842
Subtract 798 from 840 to get 42.
Since there are no more digits in the dividend, we add a zero to the remainder making it 420, and continue the process.

Moving on to step 16:
399 can be fit into 420 1 times, resulting in a remainder of 21.
The number 1 becomes the next digit in our result. 
Result so far: 58779.47368421
Subtracting 399 from 420 leaves us with 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

After the division, we end up with 58779.47368421 and a remainder of 2.1e-08.