$ sudo apt-get update
$ sudo apt-get install node-sphericalmercator 

node-sphericalmercator is installed in your system.

Make ensure the node-sphericalmercator package were installed using the commands given below,

$ sudo dpkg-query -l | grep node-sphericalmercator *

You will get with node-sphericalmercator package name, version, architecture and description in a table

node-sphericalmercator package basic information: