Complete a reCAPTCHA form to make a phone-call

I'd like people to contact me from my personal page (which is mobile and desktop friendly), but I don't want my cell phone number scraped by bots. So I thought I could have users visiting my page check off the Google reCAPTCHA form to get access to my phone number.

<form action="?" method="POST">
  <div class="g-recaptcha" data-sitekey="6Lc5XQ4TAAAAAN18KgCH-E-tVEVnzwP80NDX9v9Q"></div>
  <br/>
  <input type="submit" value="Submit">
</form>

So what do I do put for the form action? I don't want my number there using the "tel:" standard because then my number is still visible in the source code.

In summary, I'm just wondering what's the best way to programmatically instantiate a phone call without revealing the phone number or allowing bots to scrape.

Thanks in advance!