Can I change the routing number I entered after filing

Did you already e-file?  If you did NOT e-file you can go to the FILE section and change how you want to receive your refund.

Once a return has been accepted by the IRS you cannot change how you want to receive your refund.

If you e-filed:

Banking information for direct deposit is wrong

If you entered incorrect banking information for your refund, you can change it if your return is rejected.  If it is accepted, however, it is too late to change it.  The bank will reject the refund and send it back to the IRS.  Then the IRS will issue a paper check and mail it to the address you put on your tax return.  Expect a delay of at least a couple of weeks to receive your refund.

Here is what the IRS says about entering incorrect banking information

https://www.irs.gov/help-resources/tools-faqs/faqs-for-individuals/frequently-asked-tax-questions-answers/irs-procedures/refund-inquiries/refund-inquiries-18