apt install apt-transport-https curl
curl -s https://deb.nodesource.com/gpgkey/nodesource.gpg.key | apt-key add -
echo "deb https://deb.nodesource.com/node_6.x jessie main" > /etc/apt/sources.list.d/nodesource.list
echo "deb-src https://deb.nodesource.com/node_6.x jessie main" >> /etc/apt/sources.list.d/nodesource.list
Note that the version 6.x is current LTS. You can change it to 7.x for latest node version. Look at LTS schedule for more information.
apt update && apt install nodejs
thanks!