What is the highest number that can be got from 4383 by moving exactly 2 matches? What is the highest number that can be got from 4383 by moving exactly 2 matches?
Number 1 has got 2 matches, so I thought it will be 47831 as I remove two matches from second number (3), but it isn't the highest possible.
Format is same like this (1 is only number with only two matches)

Does anybody know solution?
 A: I am guessing 71393. Rotate the horizontal match of the leading 4 to split it into two ones, and grab one out of the 8 to turn the leading 1 into a 7.
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A: Tetration notation:
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or (if that's not a valid $9$),
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$^{438}3= 3^{3^{\cdot^{\cdot^{3^3}}}}$ (an exponential tower with $438\ \ 3$s).
A: If you want to play with notation, you could have 4^783 or $438^3$ depending on what you allow.
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Of course with actual matches, the caret would be squished in between the 4 and the 3.  Might be considered cheating because really you should move the whole 4, as I did in the drawing.  On the other hand:
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Only moves 2 matches and would be how you would write $438^3 = 84,027,672$
A: 7^983 is the highest number.  The 4 changes to a 7, and the 3 changes to a 9.
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