1491
1491 is a year in the 15th century. The marriage of Charles VIII and Anne of Brittany began the union of Brittany with France (France).
- Odd
- Composite
Where 1491 fits
Why 1491 is special
1491 has a profile because of what happened in it rather than because of any property of the number: the marriage of Charles VIII and Anne of Brittany began the union of Brittany with France (France).
1491 is part of
Factors & digit properties
- Divisors (8)
- 1, 3, 7, 21, 71, 213, 497, 1491
- Prime factorisation
- 3 × 7 × 71
- Digit sum
- 15
- Digital root
- 6
Representations
- Decimal
- 1491
- Scientific notation
- 1.491 × 10^3
Roman numerals
M C D X C I
MCDXCI uses the subtractive pair XC: ten before a hundred — a hundred minus ten.
Binary
1 0 1 1 1 0 1 0 0 1 1
1 × 1,024 + 0 × 512 + 1 × 256 + 1 × 128 + 1 × 64 + 0 × 32 + 1 × 16 + 0 × 8 + 0 × 4 + 1 × 2 + 1 × 1 = 1,491
Octal
2 7 2 3
2 × 512 + 7 × 64 + 2 × 8 + 3 × 1 = 1,491
Hexadecimal
5 d 3
5 × 256 + d × 16 + 3 × 1 = 1,491
Read as powers of two: 1,024 + 256 + 128 + 64 + 16 + 2 + 1 = 1,491.
In historical numeral systems
Egyptian
1 lotus, 4 coils of rope, 9 hobbles, 1 stroke
1 × 1,000 + 4 × 100 + 9 × 10 + 1 × 1 = 1,491. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
2 corner wedges + 4 vertical wedges (sixties place), 5 corner wedges + 1 vertical wedge (units place)
24 × 60 + 51 = 1491. 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
- Lucky number (mathematical sieve)
Related numbers & connections
1491 is a year in the 15th century, in the 1490s.
Numbers Around Us
- appears inHistorical years
why?
Strength 0.50, confidence "high".
History
In 1491, the marriage of Charles VIII and Anne of Brittany began the union of Brittany with France (France).
DocumentedHistoryGeography: FrancePeriod: 1491
Common questions
Is 1491 a prime number?
No, 1491 is not prime.
What are the factors of 1491?
The factors of 1491 are 1, 3, 7, 21, 71, 213, 497, 1491.
What is 1491 in Roman numerals?
1491 in Roman numerals is MCDXCI. XC is subtractive: ten before a hundred — a hundred minus ten. Written additively it would be MCCCCLXXXXI, which Roman inscriptions used freely — the strict subtractive form is a later convention.
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