* Varying Definitions: What constitutes an "irregular" verb can be subjective. Some verbs have slight variations in their conjugation that might not be considered truly irregular by all.
* Degrees of Irregularity: Some verbs are highly irregular (e.g., "ser" - to be, "ir" - to go), while others might only have one or two irregular forms.
* Regional Variations: Portuguese has several regional variations, and some verbs may be considered irregular in one dialect but not in another.
However, it's safe to say that Portuguese has a significant number of irregular verbs. It's estimated that there are hundreds of irregular verbs, and learning them is a crucial part of mastering the language.
Instead of focusing on a specific number, concentrate on understanding the different types of irregularities and practicing the common irregular verbs.