Are the properties of anti-hydrogen opposite to those of hydrogen? In the series Crisis of Infinite Earths, the whole story is that there is a wave of antimatter rampaging through the multiverse. So I got interested and googled "how to create antimatter", and I found out that when an antiproton and a positron are present in an atom, it creates an anti-hydrogen atom. My question is, what is anti-hydrogen? What can be its properties? We all know that hydrogen is flammable, so is anti-hydrogen a non-flammable material? Because it has opposite properties, right?
 A: 
In particle physics, every type of particle is associated with an antiparticle with the same mass but with opposite physical charges (such as electric charge)

Bold mine. Note physical charges. There are specific numbers associated with elementary particles that define them, and those are the ones reversed, as  in the proton antiproton case, or the electron positron case.
A world made completely out of antimatter would have the same chemical and electric etc interactions.

We all know that hydrogen is flammable, so is anti-hydrogen a non-flammable material? Because it has opposite properties, right?

The "opposite" does not go to interactions, only to quantum numbers. So yes  antihydrogen it would be flammable in an antimatter world. There is an ongoing search to see whether antimatter exists in bulk in our universe .
A: The properties of anti-matter in general are very similar to properties of matter. Richard Feynman considered the problem of if we made radio contact with an alien civilization, how would we be able to tell if they were made of matter or anti-matter? It turns out to be a complicated process. See 52-8.
Anti-hydrogen is very much like hydrogen. It would combine with anti-oxygen to make anti-water (I am making up names, but it should be clear what I mean.) Anti-water could support life just like water. Anti-people would be made of familiar anti-elements, which would have the same chemistry as elements.
The only difference between anti-hydrogen and hydrogen is that it is made of an anti-electron (or positron) and an anti-proton. The only difference between an anti-electronand an electron is the anti-electron has a positive charge instead of negative. Likewise an anti-proton has a negative change instead of positive.
Anti-electrons repel each other just like electrons do. Anti-electrons are attracted to anti-protons, just like electrons and protons attract.
Anti-electrons in anti-atoms would interact with each other in the same kind of way as electrons in atoms do, and would form the same kinds of chemical bonds.
As long as anti-matter and matter don't come in contact, they pretty much have identical behavior. Of course, if they do come in contact, they annihilate each other in a flash of gamma rays.
