1365
NGC 1365 is the Great Barred Spiral.
- Odd
- Composite
Where 1365 fits
Why 1365 is special
Its bar is long enough that gas funnelled along it feeds an active nucleus, which is the clearest observed case of a bar driving a black hole.
Factors & digit properties
- Divisors (16)
- 1, 3, 5, 7, 13, 15, 21, 35, 39, 65, 91, 105, 195, 273, 455, 1365
- Prime factorisation
- 3 × 5 × 7 × 13
- Digit sum
- 15
- Digital root
- 6
Representations
- Decimal
- 1365
- Binary
- 10101010101
- Octal
- 2525
- Hexadecimal
- 555
- Roman numeral
- MCCCLXV
- Scientific notation
- 1.365 × 10^3
Other mathematical patterns
- Deficient number
- Harshad (Niven) number
- Lucky number (mathematical sieve)
Related numbers & connections
Both are barred spirals used as reference examples, one for clean morphology and one for a bar visibly feeding a nucleus.
View 1300 →Both show gas driven inward along a bar, one feeding an active nucleus and one piling up in a star-forming ring.
View 1097 →Science
NGC 1365 in the Fornax cluster has a prominent bar and an active galactic nucleus, and is a standard case for studying bar-driven gas inflow.
DocumentedSciencePeriod: 1826–
Common questions
Is 1365 a prime number?
No, 1365 is not prime.
What are the factors of 1365?
The factors of 1365 are 1, 3, 5, 7, 13, 15, 21, 35, 39, 65, 91, 105, 195, 273, 455, 1365.
What is 1365 in Roman numerals?
1365 in Roman numerals is MCCCLXV.
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: 3 August 2026