Apex domains cannot have CNAME records.
Question and response
Question
dig awsdns-17.com. NS
Answer
awsdns-17.com. 5 NS g-ns-593.awsdns-17.com.
awsdns-17.com. 5 NS g-ns-18.awsdns-17.com.
awsdns-17.com. 5 NS g-ns-1745.awsdns-17.com.
awsdns-17.com. 5 NS g-ns-1169.awsdns-17.com.
Authority
The response has no authority records.
Additional
g-ns-18.awsdns-17.com. 5 A 205.251.192.18
g-ns-593.awsdns-17.com. 5 A 205.251.194.81
g-ns-1169.awsdns-17.com. 5 A 205.251.196.145
g-ns-1745.awsdns-17.com. 5 A 205.251.198.209
g-ns-18.awsdns-17.com. 5 AAAA 2600:9000:5300:1200:0:0:0:1
g-ns-593.awsdns-17.com. 5 AAAA 2600:9000:5302:5100:0:0:0:1
g-ns-1169.awsdns-17.com. 5 AAAA 2600:9000:5304:9100:0:0:0:1
g-ns-1745.awsdns-17.com. 5 AAAA 2600:9000:5306:d100:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0