congratulations they broke a
~4 bit security level key in their attempt
but jokes aside in cryptography the size is not the only thing that matters, the estimated "security level" that the keys provide is the important thing. size is only one factor that determines that level. for instance for Elliptic Curve Cryptography (ECC) the security level is half the key size but in Rivest–Shamir–Adleman (RSA) algorithm the security level is a lot lower than just half (calculated like
this).
in short you can refer to the table provided in Standards for Efficient Cryptography (SEC 1):
the achievements that this paper is about, is the Factorization they are using and the optimization that has led to which is reducing the time it takes to break RSA by a lot.