  We present detailed spectral energy distribution (SED) modeling of 14 local
ultraluminous infrared galaxies (ULIRGs) with outstanding photometric data from
the literature covering the ultraviolet--infrared (FIR) and radio bands
($\sim$50 MHz to $\sim$30 GHz). We employ the CIGALE SED fitting code to model
the ultraviolet--FIR--radio SED. For the radio-only SED modeling, we use the
UltraNest package, leveraging its nested sampling algorithm. Combining the
results from our previous study on 11 luminous infrared galaxies (LIRGs), we
discuss the global astrophysical properties of a sample of 25 starburst
galaxies (z $<$ 0.5). Their radio spectra are frequently characterized by bends
and turnovers, with no indication of ULIRGs exhibiting more complicated SEDs
than LIRGs despite showing more signs of interactions. Including radio
measurements in the CIGALE modeling constrained the dust luminosity and star
formation rate (SFR) estimates by more than 1 order of magnitude better than
previously reported for starburst galaxies. We show that total and nonthermal
radio luminosity at 1.4 and 4.8 GHz frequencies can be good estimators of
recent SFRs for all LIRGs and those ULIRGS with an insignificant influence of
active galactic nuclei. A weaker but still significant correlation is observed
between radio SFRs at 1.4 GHz and old (averaged over 100 Myr) SFRs based on SED
modeling, indicative of multiple episodes of starburst activity during their
lifetime. The thermal radio luminosity at 4.8 GHz is a better tracer of recent
star formation than the thermal luminosity at 1.4 GHz. Statistically, our
modeled nonthermal radio spectral indices do not significantly correlate with
redshift, stellar mass, SFR, specific SFR, and dust mass.
