1165
1165 is a year in the 12th century. The forged Letter of Prester John circulated, shaping European ideas of Asia and Africa for centuries (Europe).
- Odd
- Composite
Where 1165 fits
Why 1165 is special
1165 has a profile because of what happened in it rather than because of any property of the number: the forged Letter of Prester John circulated, shaping European ideas of Asia and Africa for centuries (Europe).
1165 is part of
Factors & digit properties
- Divisors (4)
- 1, 5, 233, 1165
- Prime factorisation
- 5 × 233
- Digit sum
- 13
- Digital root
- 4
Representations
- Decimal
- 1165
- Scientific notation
- 1.165 × 10^3
Roman numerals
M C L X V
Binary
1 0 0 1 0 0 0 1 1 0 1
1 × 1,024 + 0 × 512 + 0 × 256 + 1 × 128 + 0 × 64 + 0 × 32 + 0 × 16 + 1 × 8 + 1 × 4 + 0 × 2 + 1 × 1 = 1,165
Octal
2 2 1 5
2 × 512 + 2 × 64 + 1 × 8 + 5 × 1 = 1,165
Hexadecimal
4 8 d
4 × 256 + 8 × 16 + d × 1 = 1,165
Read as powers of two: 1,024 + 128 + 8 + 4 + 1 = 1,165.
In historical numeral systems
Egyptian
1 lotus, 1 coil of rope, 6 hobbles, 5 strokes
1 × 1,000 + 1 × 100 + 6 × 10 + 5 × 1 = 1,165. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
1 corner wedge + 9 vertical wedges (sixties place), 2 corner wedges + 5 vertical wedges (units place)
19 × 60 + 25 = 1165. Places are separated by a space on the tablet, with the higher place written first.
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
- Semiprime
Related numbers & connections
1165 is a year in the 12th century, in the 1160s.
Numbers Around Us
- appears inHistorical years
why?
Strength 0.50, confidence "high".
History
In 1165, the forged Letter of Prester John circulated, shaping European ideas of Asia and Africa for centuries (Europe).
DocumentedHistoryGeography: EuropePeriod: 1165
Common questions
Is 1165 a prime number?
No, 1165 is not prime.
What are the factors of 1165?
The factors of 1165 are 1, 5, 233, 1165.
What is 1165 in Roman numerals?
1165 in Roman numerals is MCLXV.
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