Many companies assume, wrongly, that once they have put up a web site, they’re done with their promotion efforts.
Your company should appear in whatever medium your customers might find you, and with a phone number. If you operate in multiiple countries, it might be multiple phone numbers.
And with responsive customer facing representatives who are knowlegeable. And, again, they might have to speak in more than one language. We in the US think English is supreme, but we get posts from all over the world in all sorts of languages, and thanks to Word Press, we can translate them all.
So, the bottom line is think about what your customers want before you forget your phone number!