Why don't you go to the source, instead of quoting other people? Here's the source:socialsecurity.gov

Republicans have spent years demonizing Social Security and spreading lies about its sustainability. They want to scare Americans and build support for making drastic cuts to the program or privatizing it entirely. Their long-term goal is to end Social Security as we know it, and convert it into a private account system which will enable Wall Street to make hundreds of billions in profits.

The truth is that, today, according to the Social Security Administration, Social Security has a $2.5 trillion surplus and can pay out every benefit owed to every eligible American for the next 25 years.

Further, because it is funded by the payroll tax and not the U.S. Treasury, Social Security has not contributed one nickel to our deficit. - Bernie Sanders