The 0's at the front can be there, but we almost never write them or use them. 4 is the same thing as 0000000000004. 1,996 is the same thing as 01,996.
We're trying to round 01,996 to the nearest ten thousand.
The 0 is in the ten thousands place. The next digit over is 1, which is less than 5, so the 0 doesn't round up.
Answer: 00,000 or just 0.