There is no sin on you for eating pig meat without intending to, because Allaah says (interpretation of the meaning):
“And there is no sin on you concerning that in which you made a mistake, except in regard to what your hearts deliberately intend. And Allaah is Ever Oft-Forgiving, Most Merciful”
And the Prophet (peace and blessings of Allaah be upon him) said: “Allaah has forgiven my ummah for mistakes, forgetfulness and that which they are forced to do.” Narrated by Ibn Maajah, 2043; classed as saheeh by al-Albaani.
The Muslim should be cautious with regard to food, especially if he is in a non-Muslim country whose people eat impure foods.
With regard to how to cleanse oneself of pig-related impurity, some scholars are of the view that it should be washed seven times, one of which should be with earth, by analogy with dogs.
But the correct view is that pig-related impurity should be washed only once. Al-Nawawi (may Allaah have mercy on him) said in his commentary on Muslim (Sharh Muslim): “Most of the scholars were of the view that pig-related impurity does not have to be washed seven times. This is the view of al-Shaafa’i, and it has the strongest evidence.”
This is what Shaykh Ibn ‘Uthaymeen thought most likely to be correct, as he said in al-Sharh al-Mumti’, 1/495): “The fuqaha’ (may Allaah have mercy on them) likened (pig-related) impurity to dog-related impurity, because pigs are dirtier than dogs, so the ruling should apply even more so.
This is a weak analogy, because pigs are mentioned in the Qur’aan and they existed at the time of the Prophet (peace and blessings of Allaah be upon him), and there is no report which likens them to dogs. So the correct view is that pig-related impurity is like any other kind of impurity, and there is no need to wash seven times, one of which should be with dust or dirt.”
See also the answer to question no. 22713.
The correct view concerning washing other types of impurity is that whatever will remove the impurity is sufficient, and there is no specific number of times it must be washed.
No matter what the correct view with regard to cleansing oneself after touching pigs, you do not have to wash any part of your bodies now, and that does not have any effect on your prayers.
And Allaah knows best.