This seems to be a widely reported problem. Are there any fixes?

admin> sudo npm install npm@latest -g
ERR! path usr/lib/node_modules/npm
ERR! code EACCES
ERR! errno -13
ERR! syscall access
ERR! Error: EACCES: permission denied ???

admin> ll usr/lib/node_modules/npm
drwxr-xr-x. 4 root root 4096 Jun 14 node_modules

admin> sudo npm - v
/usr/bin/npm: No such file or directory

admin> sudo curl -L http://npmjs.org/install.sh | sudo sh
fetching: https://registry.npmjs.org/npm/-/npm-5.0.3.tgz
added 1 package and removed 84 packages in 2.082s
/usr/bin/npm -> /usr/lib/node_modules/npm/bin/npm-cli.js
+ npm@5.0.3
added 1 package in 1.345s
It worked

admin> sudo npm - v
/usr/bin/npm: No such file or directory

... It did not seem to work very well?!

if you are already root ???

i am guessing that from " admin> "

then WHY are you using "sudo" ???

also DO NOT use "rpm" to install a rpm package
use your package manager ( yum, dnf , or zypper )

then there is this error you posted
did you even read that ?

admin was made a sudoer during CentOS install, but the username was not saved to /etc/sudoers - not a biggie.

I did read the error. I also typed the error. Why would permission be denied?

admin> yum install npm
You need to be root to perform this command

admin> sudo yum install npm
Package 1: npm already installed
Nothing to do

admin> npm -v
/usr/bin/npm: No such file or directory

admin> sudo yum remove npm
admin> sudo yum install npm
admin> npm -v
3.10.10

yum installs 3.1, and the current tgz filename suggests latest is is 5.0 (maybe there is a sensible reason for that?)