The Earth has a moment of inertia, I = 8.04×10^37 kg*m^2. The Earth rotates at a moderate angular velocity of 7.2921159 ×10^−5 radians/second.
Using Conservation of Angular Momentum we can find the new rotation of the earth.
L=I*omega= 8.04×10^37 kg*m^2 * 7.2921159 × 10^−5 = 5.86286*10^33.
5.86286*10^33 = (8.04×10^37 + 1.5424*10^22) *omega
-> solve for omega = 7.292115899502489e-05
This is 4.97511e-15 rad/s slower than earth's original rotation. This translates to 6.752*10^-10 seconds = 0.6752 nanoseconds longer per day.