Apex domains cannot have CNAME records.
Question and response
Question
dig equifax.com. NS
Answer
equifax.com. 5 NS pdns105.ultradns.org.
equifax.com. 5 NS a3-66.akam.net.
equifax.com. 5 NS a16-66.akam.net.
equifax.com. 5 NS pdns105.ultradns.com.
equifax.com. 5 NS a4-66.akam.net.
equifax.com. 5 NS a14-64.akam.net.
equifax.com. 5 NS a1-111.akam.net.
equifax.com. 5 NS pdns105.ultradns.biz.
equifax.com. 5 NS a11-64.akam.net.
equifax.com. 5 NS pdns105.ultradns.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0