Finite Group DatabasebetaFinite Group Databasebeta| order | 640 |
| nilpotency class | 1 |
| isoclinism | isoclinic class of C1 |
| automorphism | Aut(G) order 786432 |
| homology | Abelianization (H1) = G · Schur multiplier (H2) = C25×C4 |
| abelian | C22×C4×C5×C8 |
| multiplicative | (ℤ/1640)ˣ, (ℤ/1760)ˣ, (ℤ/1968)ˣ, (ℤ/2400)ˣ, (ℤ/2460)ˣ |
| subgroup | G/H | |
|---|---|---|
| center | G | C1 |
| commutator | C1 | G |
| Frattini, cosocle | C2×C4 | C24×C5 |
| socle, prime radical | C24×C5 | C2×C4 |
| LCS | G ▷ C1 | |
| UCS | C1 ◁ G | |
760 conjugacy classes of subgroups.
| minimal degree | μ(G) = 21 |
| transitive degree | μt(G) = 640 |
A minimal faithful permutation representation — 4 generators on 21 points:
(1,2,3,4,5,6,7,8)(17,18,19,20,21);(9,10,11,12);(13,14);(15,16)640 conjugacy classes. The character table is too large to display.
Construct this group in GAP via the SmallGroups library:
gap> SmallGroup(640, 18546);