Compared for example to a proton, the Planck particle is extremely small (its radius being equal to the Planck length, which is 10-20 times the proton's radius) and heavy (the Planck mass being 13 quintillion times the proton's mass).
It is thought that such particle would vanish in Hawking radiation, so that it would, in principle, have a lifetime of 1.38 ยท 10-44 seconds or 0.26 times the Planck time, smaller than could theoretically be measured. However, the existence of such radiation is disputed.
