Only one photo seems to have posted. Here is another

And one more

I don't think that is powdery mildew...that is usually fine powder-like coating. I think I see some webs too, and the big blobs - IMO, it is most likely mealy bugs. That is quite big infestation. I would immediately use some rubbing alcohol - it will actually 'melt' the white stuff, that is only protecting the bugs. If you look thru magnifying glass, all you see left will be small, orangey bugs. They will die on direct contact with rubbing alcohol. Test it to confirm: use a q-tip dipped in rubbing alcohol and swipe over any of the blobs, lets say on the flower stalk - see what happens...

Bugs, not mildew. Put them under running water to remove most of them, or immerse the whole thing in a bucket of water for 10 minutes. The critters should float to the top. If there are any stragglers, go after them with the Q-tip and alcohol.

I second that (mealybugs). Are you feeding your succulents any nitrogen? That can make these bugs take off like rockets.

I like to spray on a 50/50 mix of rubbing alcohol and water. Look at the other plants in your collection to see if you have further problems.

100% that's Mealy Bug.