What are some examples of dystopian characteristics?

The story The Twenty-One Balloons is a story about a utopia, but the question asks about what are some dystopian characteristics. I'll provide information about typical dystopian characteristics, and they can be contrasted with a utopia.  
The Merriam-Webster dictionary gives the following definition for "dystopia."  

An imaginary place where people lead dehumanized and often fearful lives.

That's a fairly limited and broad definition. It doesn't provide typical features that cause the citizens to be dehumanized and fearful. The following elements are typical features of many dystopian societies.  
Propaganda is used heavily to control citizens. 
Citizens have a fear of the outside world or other societies.  
Information, freedom, and independent thought are restricted.  This is completely different in The Twenty-One Balloons. The story emphasizes the themes of creativity, individuality, and cooperation.
Citizens conform to uniform expectations. Individuality and dissent are not promoted. 
The citizens are under constant surveillance, or they believe that they are. 
Some kind of leader, figurehead, or concept is supposed to be worshiped by the citizens. 
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