66003 ÷ 2 = 33001 R1
Let's divide 66003 by 2.

Step 1:
2 goes into 6 3 times with a remainder of 0.
Write down 3 as next digit of of the result. 
Result so far: 3
Subtract 6 from 6 to get 0.
Bring next digit (6) of the dividend behind the 0 and repeat the process: 6 / 2

Step 2:
2 goes into 6 3 times with a remainder of 0.
Write down 3 as next digit of of the result. 
Result so far: 33
Subtract 6 from 6 to get 0.
Bring next digit (0) of the dividend behind the 0 and repeat the process: 0 / 2

Step 3:
2 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of of the result. 
Result so far: 330
Subtract 0 from 0 to get 0.
Bring next digit (0) of the dividend behind the 0 and repeat the process: 0 / 2

Step 4:
2 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of of the result. 
Result so far: 3300
Subtract 0 from 0 to get 0.
Bring next digit (3) of the dividend behind the 0 and repeat the process: 3 / 2

Step 5:
2 goes into 3 1 times with a remainder of 1.
Write down 1 as next digit of of the result. 
Result so far: 33001
Subtract 2 from 3 to get 1.

The final result is 33001 with a remainder of 1.