I'd email the editor of the journal and let her or him know of the error.

Request the editor for publishing erratum.

Yes, the solution is to publish an erratum by requesting the editor of that particular journal. Please refer an example of erratum in the attachment.

You will have to publish an erratum as the publisher won't simply change the typo of an already published article unfortunately. For one of my previous paper, the publisher accidentally published the colour legend of a contour plot as only white... and I mean the online version.