I say ‘in Germany’ because there’s where I reside, a welfare state.
We don’t have 401K here, but public retirement systems, mandatory.
My employer also matches what I put in a small state pension system up to 50 euros. Not really much, better than nothing.
What number do I have to reach for a decent retirement? Retirement age: 67 years old.
Is it enough to save or do I have to invest?
Also consider the form of these savings. Keeping everything in financial assets might be very dangerous on the very long term. The chances of a world war and/or a financial collapse of the West are relatively high and you don’t want a hyperinflation crisis to destroy all your savings. It happened in Germany, it is happening again in some parts of the world, it will happen again.