= Solution
The <magnetic torque> transfers <angular momentum> from the faster rotator to the slower one. When $\Omega_m>\Omega_K(r_m)$, the <neutron star> supplies <angular momentum> to the inner <accretion disk> and possible <propeller flow>, so it tends to \b[spin down]. When the inner <accretion disk> rotates faster than the star, the magnetic connection and accreted <angular momentum> tend to \b[spin it up].
For slowly varying <mass accretion rate> and <magnetic dipole moment>, these tendencies favour a <magnetic spin equilibrium> with the <corotation radius> near the <magnetospheric truncation radius>:
$$
\boxed{\Omega_{\rm eq}\sim\left(\frac{GM}{r_m^3}\right)^{1/2},\qquad
P_{\rm eq}\sim\frac{2\pi\epsilon^{3/7}\mu^{6/7}}{(GM)^{5/7}\dot M^{3/7}}.}
$$
The precise balance depends on accreted and ejected <angular momentum> and on the extent of magnetic coupling across the <accretion disk>; corotation is a scaling estimate, not an exact zero-torque theorem.
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