25161813 ÷ 400 
Our goal is to divide 25161813 by 400.

Going ahead to step 1:
400 goes into 2 0 times with a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Bring next digit (5) of the dividend behind the 2 and repeat the process: 25 / 400

On to step 2:
25 divided by 400 is 0 with a remainder of 25.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 25, we end up with 25.
Append the next digit (1) from the dividend to 25 and continue with: 251 / 400

Advancing to step 3:
400 goes into 251 0 times with a remainder of 251.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 251 and we're left with 251.
Include the next digit (6) from the dividend after 251, then repeat: 2516 / 400

Let's proceed to step 4:
The number 400 fits into 2516 6 times, leaving a remainder of 116.
Write down 6 as next digit of the result. 
Result so far: 6.0
If we subtract 2400 from 2516, we get 116.
Fetch the next digit (1) from the dividend, attach it to 116 and continue: 1161 / 400

Moving on to step 5:
1161 divided by 400 is 2 with a remainder of 361.
Write down 2 as next digit of the result. 
Result so far: 62.0
If we take 800 away from 1161, we end up with 361.
Append the next digit (8) from the dividend to 361 and continue with: 3618 / 400

Let's proceed to step 6:
3618 divided by 400 is 9 with a remainder of 18.
Put 9 as the next digit of the answer. 
Result so far: 629.0
If we subtract 3600 from 3618, we get 18.
Fetch the next digit (1) from the dividend, attach it to 18 and continue: 181 / 400

Let's proceed to step 7:
When dividing 181 by 400, we get 0 with a remainder of 181.
Put 0 as the next digit of the answer. 
Result so far: 6290.0
If we take 0 away from 181, we end up with 181.
Bring next digit (3) of the dividend behind the 181 and repeat the process: 1813 / 400

Step 8:
400 goes into 1813 4 times with a remainder of 213.
Record the quotient 4 as the next digit in the result. 
Result so far: 62904.0
Subtract 1600 from 1813 to get 213.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2130, and continue the process.

Let's proceed to step 9:
If we divide 2130 by 400, we get 5 and a remainder of 130.
The next digit of our result is 5. 
Result so far: 62904.5
If we take 2000 away from 2130, we end up with 130.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1300, and continue the process.

On to step 10:
1300 divided by 400 is 3 with a remainder of 100.
Use 3 as the next digit of our solution. 
Result so far: 62904.53
If we take 1200 away from 1300, we end up with 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1000, and continue the process.

Moving on to step 11:
400 can be fit into 1000 2 times, resulting in a remainder of 200.
Put 2 as the next digit of the answer. 
Result so far: 62904.532
Deduct 800 from 1000 and we're left with 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2000, and continue the process.

Going ahead to step 12:
400 goes into 2000 5 times with a remainder of 0.
Use 5 as the next digit of our solution. 
Result so far: 62904.5325
Subtracting 2000 from 2000 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 13:
If we divide 0 by 400, we get 0 and a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 62904.5325
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.

On to step 14:
When dividing 0 by 400, we get 0 with a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 62904.5325
If we subtract 0 from 0, we 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 outcome is 62904.5325, with a leftover of 0.0.