npm install throwing error in ubuntu - node.js

Question

I'm trying to install a package using npm install -g PACKAGE_NAME but it is throwing the following error.
npm http GET https://registry.npmjs.org/ionic
npm http 304 https://registry.npmjs.org/ionic
npm ERR! Error: EACCES, mkdir '/usr/local/lib/node_modules'
npm ERR! { [Error: EACCES, mkdir '/usr/local/lib/node_modules']
npm ERR! errno: 3,
npm ERR! code: 'EACCES',
npm ERR! path: '/usr/local/lib/node_modules',
npm ERR! fstream_type: 'Directory',
npm ERR! fstream_path: '/usr/local/lib/node_modules/ionic',
npm ERR! fstream_class: 'DirWriter',
npm ERR! fstream_stack:
npm ERR! [ '/usr/lib/nodejs/fstream/lib/writer.js:171:23',
npm ERR! '/usr/lib/nodejs/mkdirp/index.js:37:53',
npm ERR! 'Object.oncomplete (fs.js:107:15)' ] }
npm ERR!
npm ERR! Please try running this command again as root/Administrator.
Also when I tried sudo npm install -g PACKAGE_NAME , it executed silently but the package was not installed.
$ sudo npm install -g ionic
npm http GET https://registry.npmjs.org/ionic
npm http 304 https://registry.npmjs.org/ionic
/usr/local/bin/ionic -> /usr/local/lib/node_modules/ionic/bin/ionic
ionic#1.7.13 /usr/local/lib/node_modules/ionic
xarvis#xarvis:~/songhop/self$ ionic
/usr/bin/env: node: No such file or directory
Also As stated in an answer on stack overflow I've give write access in node_module directory using sudo chown -R $USER node_modules.

Answer 1

The first error says you are not root. If you want to add node modules as user avoid -g (global) in your npm command.
The second one is saying that it cannot find node. You need to do a symbolic link from nodejs to node while installing nodejs in ubuntu as:
sudo ln -s /usr/bin/nodejs /usr/bin/node
To test your node installation, type in terminal node -v to see the node version number.