21258+3640
- Unique Name: 21258+3640S 790AB
- RA: 21 25 47.02
- Dec: +36 40 02.5
- Discoverer: S
- Discoverer Number: 790
- Components: AB
- First year: 1896
- Last year: 2012
- Observations: 12
- First position angle: 30
- Last position angle: 29
- First separation: 32.9
- Last separation: 34.7
- Mag first component: 5.89
- Mag second component: 11.71
- Spectral type: B0Ib
- Primary proper motion RA: 8
- Primary proper motion DEC: -10
- Secondary proper motion RA: 5
- Secondary proper motion DEC: 9
- Durchmusterung: +36 4557
- Notes: N D
