It's great to see you here in the Community, @MikeT23. Yes, you can change an invoice number and use your preferred numbering system.
By turning on the Custom Transaction Numbers, it lets you customize your invoice and sales numbers.
Once done, you can now change the invoice or sales numbers. Here's how:
For more information, refer to this help article: Change the number on invoices or other transactions. It includes steps on how to reset your transaction numbers in case you'll need to.
For future reference, read through this topic: How to find the duplicate invoice, estimate, or sales receipt numbers to help ensure that you're not assigning the same number to an existing invoice.
Feel free to visit and leave a comment if you have additional questions. We're always delighted to be of your service.