Identify the Missing Predecessor: What Number Comes Before 3501?

To find the number before 3501, we simply need to subtract 1 from 3501 because the problem states that "the number after me is 3501". This implies the next integer after our unknown number must be 3501.

Performing the calculation:

$\text{Unknown number} = 3501 - 1 = 3500$

Therefore, the number you are looking for is $3500$.