20561 ÷ 2 = 10280 R1
No problem, we've got 20561 and 2 for the division.

Step 1:
2 goes into 2 1 times with a remainder of 0.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 2 from 2 to get 0.
Bring next digit (0) of the dividend behind the 0 and repeat the process: 0 / 2

Step 2:
2 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of of the result. 
Result so far: 10
Subtract 0 from 0 to get 0.
Bring next digit (5) of the dividend behind the 0 and repeat the process: 5 / 2

Step 3:
2 goes into 5 2 times with a remainder of 1.
Write down 2 as next digit of of the result. 
Result so far: 102
Subtract 4 from 5 to get 1.
Bring next digit (6) of the dividend behind the 1 and repeat the process: 16 / 2

Step 4:
2 goes into 16 8 times with a remainder of 0.
Write down 8 as next digit of of the result. 
Result so far: 1028
Subtract 16 from 16 to get 0.
Bring next digit (1) of the dividend behind the 0 and repeat the process: 1 / 2

Step 5:
2 goes into 1 0 times with a remainder of 1.
Write down 0 as next digit of of the result. 
Result so far: 10280
Subtract 0 from 1 to get 1.

The final result is 10280 with a remainder of 1.