Ok Yeti I've did some research on that and I brought the answer for you and all here..
Your Question Was the age of Hazrat Ayesha (R.A) when she married with PROPHET HAZRAT MOHAMMAD (S.A.W)?
Narrated 'Aisha: that the Prophet(S.A.W) married her when she was six years old and he consummated his marriage when she was nine years old, and then she remained with him for nine years (i.e., till his death).
Sahih Bukhari 7:62:64
As The age is provided in the tradation of Sahih bikhari her age was 9 years old, There is no doubt on it and remain with Prophet (S.A.W) for nine years old.
As We Know that
She was the most beloved wife of Prophet Mohammad S.A.W after Hazrat Khadija R.A. Three years after the tragic and painful death of Hazrat Khadija R.A, Hazrat Khawla R.A, the wife of Hazrat Usman Mazoun R.A, suggested that Rasulallah S.A.W should remarry. In reply, Rasulallah S.A.W asked, “Who should I marry?” upon which she presented two names; one was that of Hazrat Aisha (R.A), and the other was that of Hazrat Sawda (R.A).
Rasulallah S.A.W then sent Hazrat Khawla R.A with marriage proposals to both families, and they both gave their consent. When news reached Hazrat Abu Bakr R.A, in his immense joy, he wished to clarify a point so he said to Rasulallah s.a.w, “I am your brother.” Rasulallah s.a.w then replied, “You are my brother as far as the religion and book of Allah is concerned, and she is legitimate for me.” (Bukhari) Hearing this reply, the happiness of Hazrat Abu Bakr Siddique R.A was clearly visible and he gave his consent.
Now Remember that 9 Years were left for PROPHET S.A.W at then when Married With Hazrat Ayesha (R.A).
About specialities of Hazrat Ayesha (R.A) That were the causes to be chosen for the mother of UMMAH.
In her youth, already known for her striking beauty and her formidable memory, she came under the loving care and attention of the Holy Prophet Muhammad S.A.W. As his wife and close companion she acquired from him knowledge and insight such as no woman has acquired. Mean While The age factor ,The years she had left at then before death is also one of the facter to be chosen as a mother of UMMAH. So After the Death of PROPHET(S.A.W) she have to continue the teahings of Prophet S.A.W to UMMAH.
Mother is considered as the best teacher for his child ..
For this prespective..
Hazrat Aisha’s RA students were approximately 200, out of which were: Hazrat Abu Hurairah, Hazrat Abu Musa Ashari, Hazrat Abdullah ibn Abbas and Hazrat Abdullah ibn Zubair (Radhiyallahu-Anhum). Men and women came from far and wide to benefit from her knowledge. The number of women is said to have been greater than that of men. Besides answering enquiries, she took boys and girls, some of them orphans, into her custody and trained them under her care and guidance. She conveyed the knowledge that she had comprehended and memorized. She directed people, taught them, guided them and gave them wisdom. She left a legacy that is rate to be found in others. The knowledge that she imparted formed a substantial part of the rules of Islamic jurisprudence and its principles.
It is of the greatest relevance to note the pivotal role she played as a teacher, exponent and interpreter of the religion of Islam. Aisha RA was an exceptionally intelligent and astute woman, a young prodigy, and this was the main reason why she got married to the Holy Prophet S.A.W, as is clearly proved by events after the Holy Prophet’s S.A.W life. She entered his household, shortly after his emigration to Madina, just at the time when the teachings of Islam in all fields of life for the Muslim community were starting to be revealed by the Holy Prophet S.A.W and demonstrated by his examples and practices.
After the Holy Prophet’s S.A.W death, she acted as a teacher and interpreter of Islam, providing guidance to even the greatest of the male Companions of the Holy Prophet Muhammad S.A.W. They made a special point of going to her to gain knowledge and seek her opinion. Aisha was really a generous soul and a patient one. She bore with the rest of the Prophet’s S.A.W household poverty and hunger which often lasted for long periods. For days on end no fire would be lit in the sparsely furnished house of the Prophet for cooking or baking bread and they would live merely on dates and water. Poverty did not cause her distress or humiliation. Hazrat Ayesha R.A, showered the glory and glitter of worldly things. Being in the company of the Prophet, her standards of worshipping Allah, were lofty in nature.
Aisha R.A not only possessed great knowledge but took an active part in education and social reform. As a teacher she had a clear and persuasive manner of speech and her power of oratory has been described in superlative terms by al-Ahnaf who said: “I have heard speeches of Abu Bakr and Umar, Usman and Ali and the Khulafa up to this day, but I have not heard speech more persuasive and more beautiful from the mouth of any person than from the mouth of Aisha R.A.” Hazrat Ayesha’s R.A apartment is also of great significance in the history of Islam. It is the room that houses the Prophet’s grave and his noble body. It is the only room of the Prophet’s S.A.W wives that still exists. It is the room where Hazrat Ayesha R.A nursed the Prophet S.A.W when he was sick. It is the room that shelters the remains of two of his closest companions and commanders of the faithful – Hazrat Abu Bakr R.A and Hazrat Umar R.A (May Allah be pleased with them).
During his final illness, it was at Hazrat Aisha’s R.A apartment that he went at the suggestion of his wives. When the Holy Prophet S.A.W was on his death bed, he had his head on Hazrat Aisha’s R.A lap. At the time of the Holy Prophet Muhammad’s S.A.W death she was only eighteen years old. Hazrat Ayesha R.A, in the month of Ramazan on its seventeenth (17th) day, in the year 58 AH, at the age of sixty six surrendered her soul and was buried the same night in Jannatul Baqee, after Salat Al-Witr. (May Allah be pleased with her).