"Safe" in what sense?
And don’t you think the specifics (OS, processor, GPU, …) of your laptop might be of relevance?
Safe as in virus free and slowing down my computer? I have Dell Inspiron 3521 Processor : Intel (I) Pentium (R) CPU 2117U
As the Dell Inspiron 3521 is a budget machine with a max of 4GB of RAM, I'd suggest it will not be the best fit for running Photoshop.
But if your system meets the basic requirements, and you'd like to know for sure, download the free trial and try it. You can always fully clean it back off your system later with something like the Creative Cloud Removal tool.