I’ve been reading a lot of Krimis written for those learning German and came across the word gestehen in one of them (http://www.klett.de/produkt/isbn/3-12-675496-1). It means “to confess” and it joins the small family of verbs I know that happen look like past participles: gefallen and gehören – “to be pleasing [to someone]” and “to belong [to someone].” In the case of gefallen,it is both an infinitive and a past participle (for fallen); the past participle of both gehören and hören is gehört and the past participle of both stehen and gestehen is gestanden. One factor that has helped me keep clear on gefallen and gehören is that they require use of the dative: das gefällt mir and das gehört mir – “that pleases me” and “that belongs to me.” Using cannoo.net, I discovered that there are 25 verbs which are formed by the addition of the prefix ge- (http://www.canoo.net/services/WordformationRules/Controller?wordFormationClass=Verb-zu-Verb-Ableitungen+mit+dem+Pr%E4fix+ge&entryClass=Cat+V&resultId=99dc65). Given there are 18202 verbs in the cannoo database, this makes it a rather rare prefix. (One verb I might have expected to see on this list is genießen (“to enjoy”), however while there is niesen – “to sneeze” – there is no nießen.)
Offen gestanden, or “to tell you the truth,” I usually still have a moment of confusion when I hear gehört and need to pause to discern whether we are talking about a case of “hearing” or a case of “belonging” (which just now brought to mind die Belohnung – “the reward” – of which getting the meaning surely is it’s own!).