21170+4020
- Unique Name: 21170+4020SEI1487
- RA: 21 16 59.44
- Dec: +40 19 56.7
- Discoverer: SEI
- Discoverer Number: 1487
- Components:
- First year: 1895
- Last year: 2002
- Observations: 7
- First position angle: 240
- Last position angle: 239
- First separation: 20.7
- Last separation: 21.1
- Mag first component: 9.53
- Mag second component: 11.54
- Spectral type: A2
- Primary proper motion RA: 0
- Primary proper motion DEC: 0
- Secondary proper motion RA: -2
- Secondary proper motion DEC: -7
- Durchmusterung: +39 4506
- Notes: N
