Who is a righteous person according to the Bible?

Does a righteous person have to perfect to be considered righteous?

"And it shall be our righteousness, if we observe to do all these commandments before the LORD our God, as he hath commanded us." (Deuteronomy 6:25 KJV) 

"My tongue shall speak of thy word: for all thy commandments are righteousness." (Psalm 119:172 KJV) 

"But we are all as an unclean thing, and all our righteousnesses are as filthy rags; and we all do fade as a leaf; and our iniquities, like the wind, have taken us away." (Isaiah 64:6 KJV) 

"For a just man falleth seven times, and riseth up again: but the wicked shall fall into mischief." (Proverbs 24:16 KJV) 

"For there is not a just man upon earth, that doeth good, and sinneth not." (Ecclesiastes 7:20 KJV)

"If we say that we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness. If we say that we have not sinned, we make him a liar, and his word is not in us." (1 John 1:8-10 KJV) 

"Little children, let no man deceive you: he that doeth righteousness is righteous, even as he is righteous. He that committeth sin is of the devil; for the devil sinneth from the beginning. For this purpose the Son of God was manifested, that he might destroy the works of the devil. Whosoever is born of God doth not commit sin; for his seed remaineth in him: and he cannot sin, because he is born of God. In this the children of God are manifest, and the children of the devil: whosoever doeth not righteousness is not of God, neither he that loveth not his brother." (1 John 3:7-10 KJV) 

Ezekiel 18 and Proverbs 31:10-31; Titus 2:2-5