  We present the results of a detailed multi-wavelength study of a sample of
sixteen narrow-line Seyfert 1 (NLSy1) galaxies known in $\gamma$-rays so far.
This includes a focused X-ray spectral analysis, to compare them with a more
general NLSy1 population, and a broadband spectral energy distribution (SED)
modeling considering the leptonic radiative processes to understand their
similarity/dissimilarity with blazars. The X-ray spectra of $\gamma$-NLSy1
galaxies exhibit similarities both with typical NLSy1 sources below $\lesssim$2
keV and blazars at higher energies. We also find weak evidences of excess
absorption in the soft X-ray spectra of 3 sources and a tentative detection of
Fe line in 1H~0323+342. A comparison of the broadband parameters derived from
the SED modeling reveals the similarity of $\gamma$-NLSy1 objects with blazars,
in particular more with flat spectrum radio quasars. The $\gamma$-NLS1 galaxies
host relatively low power jets with small bulk Lorentz factors with respect to
blazars and this explains the paucity of such sources in the $\gamma$-ray
catalogs and identification of an even fewer parent population members. Many of
the observed features of these intriguing objects suggest they host low-mass
black holes. The accretion rate in Eddington units can be considered as the
driving factor to explain the physical properties of $\gamma$-NLSy1 sources,
similar to that which is known for general blazar population.
