for direct deposit, two items are needed
1) the bank routing number (BRN) which is always 9 digits in US
2) your account number
There is virtually no possibility that these two numbers are the same.
if you have a check the BRN is at the bottom to the far left. the account number would be n the center or on the right
if you can't find the BRN call them.
a bad BRN or account number would result in the DD being rejected and sent back to the IRS to mail you a paper check.