Christian or atheist

Is it better to be a Christian sinner or a righteous atheist? I heard a Catholic say it is better to be a righteous atheist.

Christians are sinners who, through faith in Jesus Christ, enjoy forgiveness of sins. Atheists are people who cannot do anything righteous in God’s sight or pleasing to him (John 15:5; Hebrews 11:6).

Jesus’ words in Mark 16:16 (“Whoever believes and is baptized will be saved, but whoever does not believe will be condemned.”) answer your question very clearly.