In Buddhism there are four maras. The mara of delusions, the mara of death, the mara of contaminated aggregates, and Devaputra mara. Only the last of these is a 'living being' so to speak. Devaputra Mara is regarded as a malevolent spirit that resides in a certain god realm called 'Controlling Others Emanations'. He has many powers or qualities that enable him to influence others. In general, his nature is to engage in destructive behaviors, such as causing accidents or increasing the delusions people have. His influence is very complex as he has control over things like the elements, and is able to influence not only our minds but can manifest things within our body. He has many spirits under his control that assist in his misdeeds. Nonetheless, he has Buddhanature and therefore he can and will eventually become enlightened. The compassion of Buddhas is not partial to one particular ethnicity or type of living being. All living beings are worthy of love and compassion.
Devaputra has been generally equated with Satan, but I think this probably only applies with regards to similarities in actions, but even that is difficult to say since there are so many different interpretations of Satan, the Devil, Baphomet, the Green Man, Abraxis etc etc. People mostly seem to use the term Satan or Devil in society to refer a very specific character referred to in Christian Mythology, but as I said, there are many different understandings of Satan, just as there are many interpretations of Christ and God. Even in the Bible it seems there are many different gods being referred to. For instance, there is a god that loves all his children, and there is a god who is very partial, has a specific group of people known as the 'chosen ones', and unleashes wrath that destroys people, yet there is a compassionate god and so on.
Anyways, although there may be some similarities, we cannot say that Devaputra and Satan are equivalent.