Apex domains cannot have CNAME records.
Question and response
Question
dig akamaitechnologies.com. NS
Answer
akamaitechnologies.com. 5 NS ns2-32.akamaistream.net.
akamaitechnologies.com. 5 NS ns3-32.akamaistream.net.
akamaitechnologies.com. 5 NS ax2.akamaistream.net.
akamaitechnologies.com. 5 NS ax1.akamaistream.net.
akamaitechnologies.com. 5 NS ax3.akamaistream.net.
akamaitechnologies.com. 5 NS p6.akamaistream.net.
akamaitechnologies.com. 5 NS p8.akamaistream.net.
akamaitechnologies.com. 5 NS p7.akamaistream.net.
akamaitechnologies.com. 5 NS ax0.akamaistream.net.
akamaitechnologies.com. 5 NS p5.akamaistream.net.
akamaitechnologies.com. 5 NS ns6-32.akamaistream.net.
Authority
The response has no authority records.
Additional
p5.akamaistream.net. 5 A 193.108.88.66
p6.akamaistream.net. 5 A 95.100.175.32
p7.akamaistream.net. 5 A 95.101.36.32
p8.akamaistream.net. 5 A 23.74.25.32
ax0.akamaistream.net. 5 A 72.246.46.32
ax1.akamaistream.net. 5 A 184.26.161.32
ax2.akamaistream.net. 5 A 95.100.174.35
ax3.akamaistream.net. 5 A 96.7.49.32
ns2-32.akamaistream.net. 5 A 2.22.230.32
ns3-32.akamaistream.net. 5 A 23.61.199.32
ns6-32.akamaistream.net. 5 A 95.100.168.32
p7.akamaistream.net. 5 AAAA 2600:1480:4800:0:0:0:0:20
ns3-32.akamaistream.net. 5 AAAA 2600:1406:32:0:0:0:0:20
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0