Can You Find the Prime Factors of m Using Euler's Totient Function?

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The discussion centers on the relationship between the number m, defined as the product of two prime numbers p and q, and Euler's Totient Function, Φ(m). It is established that if m = pq, then Φ(m) = (p-1)(q-1). The key insight is that knowing both m and Φ(m) allows for the deduction of p and q through the quadratic equation x² - Sx + m = 0, where S = m - Φ(m) + 1 = p + q. This method avoids brute force factorization.

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squire636
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I understand that for m = pq where p and q are prime numbers, \Phi(m) = (p-1)(q-1). Is there any way that, knowing the numerical value of m and \Phi(m), we could deduce p and q, the prime factors of m?

Thanks!
 
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Specifically, I know that a huge number m is the product of two primes and I know \Phi(m)...but I can't figure out which primes those are and I don't want to figure it out by brute force.
 
If you know m=pq and Φ=(p-1)(q-1), then define S=m-Φ+1=p+q.

So you have the product m and the sum S.
That means p and q are the solutions of the quadratic x2 - Sx + m = 0.
 

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