Valdivia is a non-family asteroid from the main belt's background population. It orbits the Sun in the central main-belt at a distance of 2.1–3.1 AU once every 4 years and 3 months (1,540 days). Its orbit has an eccentricity of 0.18 and an inclination of 10° with respect to the ecliptic.
The asteroid was first identified as 1935 CM at Uccle Observatory in February 1935, where the body's observation arc begins just a two weeks later, or more than 40 years before its official discovery observation at Cerro El Roble.
In August 2016, the so-far best-rated rotational lightcurve of Valdivia was obtained by the Spanish amateur astronomer group OBAS. Lightcurve analysis gave a rotation period of 4.098 hours with a brightness variation of 0.25 magnitude (U=3). Previously, in May 2003, photometric observations made by Donald P. Pray at the Carbuncle Hill Observatory (912) near Providence, Rhode Island, gave a synodic period of 4.096 hours and an amplitude of 0.40 in magnitude (U=2+).
In addition astronomers at the Palomar Transient Factory found a period of 4.096 hours with an amplitude of 0.28 om May 2011 (U=2), and French amateur astronomer René Roy obtained a period of 8.1922 hours (twice the period solution) with an amplitude of 0.36 (U=2).
In 2016, an international study modeled a lightcurve with a concurring period of 4.09668 hours and found two spin axis of (269.0°, −31.0°) and (103.0°, −59.0°) in ecliptic coordinates (λ, β) (U=n.a.).
The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.10 – a compromise value between the carbonaceous (0.057) and stony (0.20) asteroids – and calculates a diameter of 17.52 kilometers based on an absolute magnitude of 11.9.