As much as 18 months ago now Facebook suffered a data breach where a significant number of phone numbers were obtained.
Details of more than 530 million people (including 11 million users from the UK) have now been leaked in a database online, largely consisting of mobile numbers. These have been released in the last few days and so it's timely to do a check for yourself and family members to see if any are among the numbers released. How does it help you to know? Well then you can make a reasoned decision about whether you want to consider changing your number (shock horror for all those of us who have always had the same number and can barely remember our own pins at the bank!) or not. Knowledge is power, and better to know than not.
You can use the trustworthy, free website Have I been Pwned https://www.haveibeenpwned.com to check, and while you are there, and since it is spring cleaning time... we would highly recommend also checking whether your email address has been involved in a data breach too (worth checking this regularly, and changing your email password if it has).