When something happens in a way that amazes you, use the adverb surprisingly, like when you find the kids at your new school to be surprisingly friendly. If a situation is surprising, it is completely unexpected — and you can say that it happens surprisingly.

Is surprising a noun or adjective?

From Longman Dictionary of Contemporary Englishsur‧pris‧ing /səˈpraɪzɪŋ $ sər-/ ●●● S3 W3 adjective unusual or unexpected She told me a surprising thing.

What part of speech is surprisingly?

SURPRISINGLY (adverb) definition and synonyms | Macmillan Dictionary.