21400+3605
- Unique Name: 21400+3605ES 2129
- RA: 21 40 18.96
- Dec: +36 02 53.6
- Discoverer: ES
- Discoverer Number: 2129
- Components:
- First year: 1924
- Last year: 2007
- Observations: 6
- First position angle: 310
- Last position angle: 310
- First separation: 5.0
- Last separation: 5.1
- Mag first component: 11.3
- Mag second component: 11.4
- Spectral type:
- Primary proper motion RA: 42
- Primary proper motion DEC: -27
- Secondary proper motion RA: -17
- Secondary proper motion DEC: 6
- Durchmusterung: +35 4602
- Notes: