You receive some on-line tests, even if you haven't applied for a position in the company. They will spam you until answer them. If you send them a message to find out about the position, if you receive an answer, it will take forever. All of the tests are timed and you need a calculator, but they don't tell you in advance any of that information. There are some IQ tests, very hard to solve (specially for a recruiter who usually has no math background) and some tests associated to the position they think you fit in. If you pass the tests you will continue with the interviewing process. If you don't pass, you might receive an automated email which tells you that they might contact you in the future for another position. You will have one or 2 interviews, depending on the position. All of the interviews will gather basic information. They don't ask any questions about your knowledge, experience or background.

I had to do a lot of different assessments: regarding working remotely, analytical thinking and personality. Personally, it is very time consuming. Then I had 1 screening call which was again an analytical test. For me that was overkill