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We study the X-ray emission from NGC1277, a galaxy in the core of the Perseuscluster, for which van den Bosch et al. have recently claimed the presence ofan UltraMassive Black Hole (UMBH) of mass 1.7 times 10^10 Msun, unless the IMFof the stars in the stellar bulge is extremely bottom heavy. The X-raysoriginate in a power-law component of luminosity 1.3 times 10^40 erg/s embeddedin a 1 keV thermal minicorona which has a half-light radius of about 360 pc,typical of many early-type galaxies in rich clusters of galaxies. If Bondiaccretion operated onto the UMBH from the minicorona with a radiativeefficiency of 10 per cent, then the object would appear as a quasar withluminosity 10^46 erg/s, a factor of almost 10^6 times higher than observed. Theaccretion flow must be highly radiatively inefficient, similar to past resultson M87 and NGC3115. The UMBH in NGC1277 is definitely not undergoing anysignificant growth at the present epoch. We note that there are 3 UMBHcandidates in the Perseus cluster and that the inferred present mean massdensity in UMBH could be 10^5 Msun/Mpc^3, which is 20 to 30 per cent of theestimated mean mass density of all black holes. We speculate on the impliedgrowth of UMBH and their hosts, and discuss the possibiity that extreme AGNfeedback could make all UMBH host galaxies have low stellar masses at redshiftsaround 3. Only those which end up at the centres of groups and clusters lateraccrete large stellar envelopes and become Brightest Cluster Galaxies. NGC1277and the other Perseus core UMBH, NGC1270, have not however been able to gathermore stars or gas owing to their rapid orbital motion in the cluster core.

X-ray emission from the Ultramassive Black Hole candidate NGC1277: implications and speculation on its origin