  Magnetic skyrmionium can be used as a nanometer-scale non-volatile
information carrier, which shows no skyrmion Hall effect due to its special
structure carrying zero topological charge. Here, we report the static and
dynamic properties of an isolated nanoscale skyrmionium in a frustrated
magnetic monolayer, where the skyrmionium is stabilized by competing
interactions. The frustrated skyrmionium has a size of about $10$ nm, which can
be further reduced by tuning perpendicular magnetic anisotropy or magnetic
field. It is found that the nanoscale skyrmionium driven by the damping-like
spin-orbit torque shows directional motion with a favored Bloch-type helicity.
A small driving current or magnetic field can lead to the transformation of an
unstable N\'eel-type skyrmionium to a metastable Bloch-type skyrmionium. A
large driving current may result in the distortion and collapse of the
Bloch-type skyrmionium. Our results are useful for the understanding of
frustrated skyrmionium physics, which also provide guidelines for the design of
spintronic devices based on topological spin textures.
