This hadith clearly proves that the four women who were mentioned holding special status among all the women of the world.
Annas bin Malik narrated the Holy Prophet(pbuh) said “This is end of for you (to tell you) four women among all the women of the world Mariam bint Imran, Khadija bint Khuwalid, Fatima bint Muhammad and Asia (wife of the Pharoah)”
This hadith is graded as Sahih.
Here is another narration
Ali ibn Abi talib narrated
“I heard from the Holy Prophet (pbuh) saying this that Khadija was the best women among all the women of her time and Mariam bint Imran (mother of Jesus) was the best women among all the women of her time”
This hadith is graded as Hassan Sahih.
Aisha(wife of the Prophet) narrated “I never get jealous on anyone more than Khadija, when the Prophet (pbuh) married me she was already dead. This was the reason of my jealousy that Prophet gave her good news that she have home in heaven made of pearls and there is no hastle and disturbance.”
This hadith is graded as Hassan Hadith