Using our own observations at 45 MHz and data found in the literature after
an exhaustive search, we have attempted a comprehensive study of the integ
rated flux density spectrum of the Centaurus A radio galaxy and of its larg
e scale components. The spectrum for the whole object, between 10 and 4750
MHz, can be well represented by a power law with a spectral index of -0.70
+/- 0.01, disproving the existence of a spectral break reported by other au
thors in the past. Between 406 and 4750 MHz we present, for the first time,
the spectra of the individual Giant Outer Lobes and find that, within the
errors of measurement, their spectral indices are practically equal. We sho
w that the Giant Outer Lobes contribute with 73% of the total luminosity of
the object. That the indices of the different large scale components are c
lose or equal supports the double injection hypothesis for their origin. We
discuss the spectral indices and luminosities, and we determine upper boun
ds for the ages of the radiating electrons. We show that Centaurus A suppor
ts the P-alpha rather than the z-alpha: correlation.