Safari on iPhone tries to detect phone numbers in text and converts them into clickable links to trigger a phone call. If your site contains numbers similar to phone numbers, you must prevent Safari from converting them into links.
Either put a HTML inside the number or use META tag to disable the detection globally.
To manually create clickable phone number, use link with href "tel:+123456". Note: clicking such link on iPad or iPhone Simulator will say "Cannot open page".
Correct Phone: 1123456 (link to tel:+1123456)
Autodetected Phone: 1123456 (works only on iPhone)
Not a phone: 1123456 (obfuscated with HTML tags)
This will add META tag into HTML:
<meta name="format-detection" content="telephone=no">