Short answer
In Data Quality > Property Insights, Property anomalies watches chosen properties for unexpected update volume, and Properties to review lists properties with issues by object, updated once a day. HubSpot's KB suggests using fill rates here to find low-impact properties to archive. Reports also show property insights in the report viewer's Data Quality tab.
1. The tab
My demo portal, Property Insights.

2. Before archiving
Check where a property is used first. See checking property usage.
3. Related
Manage duplicates and formatting rules.