Argument list too long - Apache

I'm following this tutorial on deploying an wordpress application inside an AWS instance http://ift.tt/JkulVk and I get an error when I do

[ec2-user@ip-10-10-1-73 ]$ find /var/www -type f -exec sudo chmod 0664 {} +
sudo: unable to execute /bin/chmod: Argument list too long
sudo: unable to execute /bin/chmod: Argument list too long

Why does this error occur?