If you got allocated a /32, then exactly that /32 is to be routed, nothing more (of course, as you don't have a right to) and nothing less. /32s that have been allocated are Provider Aggregated (PA) prefixes, as that name implies, they need to be aggregated by the provider.

As I understand it, the smallest globally routable entities are: /48 Usually a provider or organisation which handles their own addresses is a Local Internet Registry, which get's it's addresses from a Reginal Internet Registry like RIPE for Europe and a number of other regions. Those addresses are Provider Attached addresses, their is however a different kind, the Provider Independant addresses, which is for larger organisations which need their own addresses but are not a LIR. If a LIR doesn't need any bigger then /32, it get's assigned a /32, if you are requesting PI, you'll get a /48 if you can't justify that you need any more. Their are a number of infrastructure type organisations that also get /48, like root- or topleveldomain-nameservers and Internet Exchange Points. The /48 and bigger come from a different slice of addresses, then the /32 and bigger. To facilitate filtering.