Today in my research, I had to use fairly explicitly the rather tautological property of finite cyclic groups that every normal subgroup is characteristic, i.e. fixed by all automorphisms. This got me wondering:

> do (finite) groups with the property that every normal subgroup is characteristic
> have a name and/or can they be completely
> classified? Generally, has this
> property been investigated at all?

Apart from cyclic groups, some groups possessing the above property that immediately come to mind are simple groups, symmetric groups and dihedral groups of twice odd order (however not of twice even order).

Also, every quotient of a group with the above property must possess the same property.
This is as far as I got on my short walk home. I can speculate about properties that the chief series of such groups must have (and maybe even conditions in terms of the chief series that are equivalent to the above), but I will rather wait for answers, since I suspect that this property might be well studied.


  [1]: http://en.wikipedia.org/wiki/Quasidihedral_group