Can’t update Cordova and Ionic

I can't update cordova to 5.1.1 and Ionic to 1.6.4. When running

npm update -g cordova

nothing happens.

When running:

npm install -g cordova

i get:

npm WARN engine npm@1.3.4: wanted: {"node":">=0.6","npm":"1"} (current: {"node":"0.12.7","npm":"2.7.3"})
npm WARN engine cordova-js@4.0.0: wanted: {"node":"~0.10.x"} (current: {"node":"0.12.7","npm":"2.7.3"})
npm WARN engine xmlbuilder@2.2.1: wanted: {"node":"0.8.x || 0.10.x"} (current: {"node":"0.12.7","npm":"2.7.3"})
npm WARN installMany normalize-package-data was bundled with npm@1.3.4, but bundled package wasn't found in unpacked tree
/usr/bin/cordova -> /usr/lib/node_modules/cordova/bin/cordova
cordova@5.1.1 /usr/lib/node_modules/cordova
├── underscore@1.7.0
├── q@1.0.1
├── nopt@3.0.1 (abbrev@1.0.7)
└── cordova-lib@5.1.1 (valid-identifier@0.0.1, osenv@0.1.0, properties-parser@0.2.3, bplist-parser@0.0.6, mime@1.2.11, unorm@1.3.3, semver@2.1.0, shelljs@0.3.0, dep-graph@1.1.0, rc@0.5.2, npmconf@0.1.16, through2@0.6.3, xcode@0.6.7, elementtree@0.1.6, d8@0.4.4, request@2.47.0, tar@1.0.2, glob@4.0.6, cordova-registry-mapper@1.1.9, init-package-json@1.7.1, plist@1.1.0, cordova-app-hello-world@3.9.0, npm@1.3.4, cordova-js@4.0.0)

Also Ionic reminds me to update:

Ionic CLI is out of date:
 * Locally installed version: 1.3.14
 * Latest version: 1.6.4
 * https://github.com/driftyco/ionic-cli/blob/master/CHANGELOG.md
 * Run npm install -g ionic to update

But i can't do it.

After installing Cordova and Ionic i still have

cordova -v
4.3.0

and

ionic -v
1.3.14

How can i update?

I'm running Ubuntu 15.04.