You might be looking to pad your values with some zeros, but can't quite find an easy way to do so. Here is a quick way to achieve what you might want. In this particular example, we will be padding the left side of account numbers to lead with zeros.
Here we have an 'Account' field where the values are any length. I am looking to pad any of these numbers with leading zeros as long as the length is 7 characters long.
Note: By left padding numbers, you will be changing what might be perceived as a numerical value to a string value. By doing so, you forfeit functionality reserved for numeric analysis (like filtering types, etc.),
In this 'Account.' field, I am working with a numeric field, so I'm going to write a formula that also includes a type conversion to string.