We divide 16621217 by 431
The aim is to understand the frequency of 431 in 16621217.

Moving on to step 1:
When dividing 1 by 431, we get 0 with a remainder of 1.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 1, we end up with 1.
Fetch the next digit (6) from the dividend, attach it to 1 and continue: 16 / 431

Step 2:
The number 431 fits into 16 0 times, leaving a remainder of 16.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 16, we end up with 16.
Fetch the next digit (6) from the dividend, attach it to 16 and continue: 166 / 431

Advancing to step 3:
If we divide 166 by 431, we get 0 and a remainder of 166.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 166 leaves us with 166.
Take the next digit (2) from the dividend and append it to 166, then repeat: 1662 / 431

On to step 4:
431 can be fit into 1662 3 times, resulting in a remainder of 369.
Use 3 as the next digit of our solution. 
Result so far: 3.0
Subtracting 1293 from 1662 leaves us with 369.
Bring next digit (1) of the dividend behind the 369 and repeat the process: 3691 / 431

Step 5:
431 can be fit into 3691 8 times, resulting in a remainder of 243.
Use 8 as the next digit of our solution. 
Result so far: 38.0
Subtract 3448 from 3691 to get 243.
Fetch the next digit (2) from the dividend, attach it to 243 and continue: 2432 / 431

On to step 6:
431 goes into 2432 5 times with a remainder of 277.
Use 5 as the next digit of our solution. 
Result so far: 385.0
Deduct 2155 from 2432 and we're left with 277.
Take the next digit (1) from the dividend and append it to 277, then repeat: 2771 / 431

On to step 7:
When dividing 2771 by 431, we get 6 with a remainder of 185.
Put 6 as the next digit of the answer. 
Result so far: 3856.0
Subtract 2586 from 2771 to get 185.
Grab the next digit (7) from the dividend, add it to 185, then carry on: 1857 / 431

Moving on to step 8:
431 goes into 1857 4 times with a remainder of 133.
The number 4 becomes the next digit in our result. 
Result so far: 38564.0
Deduct 1724 from 1857 and we're left with 133.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1330, and continue the process.

On to step 9:
The number 431 fits into 1330 3 times, leaving a remainder of 37.
Record the quotient 3 as the next digit in the result. 
Result so far: 38564.3
If we take 1293 away from 1330, we end up with 37.
Since there are no more digits in the dividend, we add a zero to the remainder making it 370, and continue the process.

Moving on to step 10:
431 can be fit into 370 0 times, resulting in a remainder of 370.
Record the quotient 0 as the next digit in the result. 
Result so far: 38564.3
The remainder is 370 after subtracting 0 from 370.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3700, and continue the process.

Advancing to step 11:
If we divide 3700 by 431, we get 8 and a remainder of 252.
Write down 8 as next digit of the result. 
Result so far: 38564.308
Deduct 3448 from 3700 and we're left with 252.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2520, and continue the process.

Moving on to step 12:
The number 431 fits into 2520 5 times, leaving a remainder of 365.
The next digit of our result is 5. 
Result so far: 38564.3085
Deduct 2155 from 2520 and we're left with 365.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3650, and continue the process.

On to step 13:
The number 431 fits into 3650 8 times, leaving a remainder of 202.
The number 8 becomes the next digit in our result. 
Result so far: 38564.30858
If we take 3448 away from 3650, we end up with 202.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2020, and continue the process.

Moving on to step 14:
When dividing 2020 by 431, we get 4 with a remainder of 296.
Use 4 as the next digit of our solution. 
Result so far: 38564.308584
If we take 1724 away from 2020, we end up with 296.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2960, and continue the process.

Going ahead to step 15:
If we divide 2960 by 431, we get 6 and a remainder of 374.
Put 6 as the next digit of the answer. 
Result so far: 38564.3085846
If we take 2586 away from 2960, we end up with 374.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3740, and continue the process.

Step 16:
When dividing 3740 by 431, we get 8 with a remainder of 292.
The number 8 becomes the next digit in our result. 
Result so far: 38564.30858468
Subtracting 3448 from 3740 leaves us with 292.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2920, and continue the process.

After the division, we end up with 38564.30858468 and a remainder of 2.92e-07.