You can use some tools to do that.
You probably heard about the huge breach of Facebook data where more than 533 million Facebook users in 106 countries had personal data disclosed online, including phone numbers, Facebook identifiers, dates of birth, and more.
Your first question, of course, is how to determine whether you are part of this breach. There are two or three areas where you can find out if your data has been compromised.
A well-known website which tracks data breaches is Have I Been Pwned. Simply follow the link to the website and put in your e-mail address or phone number. You will discover not only whether you have been part of the violation of Facebook, but also any other violation in which your data may have been compromised.
Troy Hunt, creator of Have I Been Pwned, was thinking about including a phone number search (as this comes with some privacy risks) but finally decided to include the functionality:
But for spam based on using phone number alone, it's gold. Not just SMS, there are heaps of services that just require a phone number these days and now there's hundreds of millions of them conveniently categorised by country with nice mail merge fields like name and gender.— Troy Hunt (@troyhunt) April 3, 2021
Another tool to check your phone number against the leaked Facebook database (suggested by Gizmodo) is a website called The News Every Day, where you input your telephone number to determine whether it is part of the breach. However, this site isn’t as well-known, so until more is known about it, you may want to stick with the more trusted site listed above.
What if you discover that your information has been compromised? Some of the actions you can take are to change the passwords of compromised websites, utilize a password manager so that you can create and follow unique passwords for each site (so that if one is compromised, it will not affect the others),utilize two-factor authentication, increase security and remain on the lookout for further violations.