5981
NGC 5981 is part of the Draco Trio.
- Odd
- Prime
Where 5981 fits
Why 5981 is special
Three galaxies appear in one field at three different orientations, which makes the group a standard demonstration of how inclination changes appearance.
5981 is part of
Factors & digit properties
- Divisors (2)
- 1, 5981
- Prime factorisation
- 5981
- Digit sum
- 23
- Digital root
- 5
Representations
- Decimal
- 5981
- Scientific notation
- 5.981 × 10^3
Roman numerals
Roman numerals as modelled here goes up to 3,999.
Binary
1 0 1 1 1 0 1 0 1 1 1 0 1
1 × 4,096 + 0 × 2,048 + 1 × 1,024 + 1 × 512 + 1 × 256 + 0 × 128 + 1 × 64 + 0 × 32 + 1 × 16 + 1 × 8 + 1 × 4 + 0 × 2 + 1 × 1 = 5,981
Octal
1 3 5 3 5
1 × 4,096 + 3 × 512 + 5 × 64 + 3 × 8 + 5 × 1 = 5,981
Hexadecimal
1 7 5 d
1 × 4,096 + 7 × 256 + 5 × 16 + d × 1 = 5,981
Read as powers of two: 4,096 + 1,024 + 512 + 256 + 64 + 16 + 8 + 4 + 1 = 5,981.
In historical numeral systems
Egyptian
5 lotuses, 9 coils of rope, 8 hobbles, 1 stroke
5 × 1,000 + 9 × 100 + 8 × 10 + 1 × 1 = 5,981. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Systems that simply cannot reach this value are left out. Where a script needs a font most readers do not have, the reading is given instead of the glyphs — see number systems for each system in full.
Other mathematical patterns
- Deficient number
Related numbers & connections
Both are edge-on spirals used to demonstrate how inclination alone changes a galaxy's appearance.
View 4565 →Other connections
- is associated with4565
why?
Strength 0.50, confidence "high".
Science
NGC 5981 is an edge-on spiral forming a visual grouping with NGC 5982 and NGC 5985, which present edge-on, elliptical and face-on appearances respectively.
DocumentedSciencePeriod: 1788–
Common questions
Is 5981 a prime number?
Yes, 5981 is prime — it has exactly two positive divisors: 1 and itself.
What are the factors of 5981?
The factors of 5981 are 1, 5981.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 1 reviewer-confirmed record, sourced and reviewed before publication.
Last reviewed: 15 July 2026