To give my opinion for this question:
- AngularJS is a MVC framework offer you the powerful two-way data binding feature that synchronize the data models and the views. You don't have this feature in React.js.
- AnguarJS is more matured than React.js. AngularJS was released in late 2010 while React.js was first launched to community in March 2013. This means when learning AnguarJS you will have access to more resources (documentation, online articles, communities, Q&A forums, books...) than React.js.
- React.js is gaining popularity (a lot more than AnguarJS) and recent versions of AnguarJS is considered to be too little too late.
- If you learn AnguarJS chances are you will see a lot of legacy projects using this framework. On other hand, for new projects React.js will be preferred.
- In an online survey in 2015, many AngularJS developers said that they had great experience with AngularJS v1 but now consider switching to React.js.
Also it's worth referencing a top comment on Reddit
If you do choose to learn ReactJS you could potentially never have to learn AngularJS, whereas I don't know for sure that you could say the opposite.
Finally, it's always based on personal preferences when comes to choosing which language, framework or library to learn or even use in a project. Whatever your choice is, chances are the your chosen technology will not likely to disappear in the market that soon (at least for several years to come).