871
871 is the year Alfred became king of Wessex.
- Odd
- Composite
Where 871 fits
Why 871 is special
He is the only English monarch called 'the Great', and the reason is administrative rather than military: burhs, a legal code, and a programme of translation into English.
Factors & digit properties
- Divisors (4)
- 1, 13, 67, 871
- Prime factorisation
- 13 × 67
- Digit sum
- 16
- Digital root
- 7
Representations
- Decimal
- 871
- Scientific notation
- 8.710 × 10^2
Roman numerals
D C C C L X X I
Binary
1 1 0 1 1 0 0 1 1 1
1 × 512 + 1 × 256 + 0 × 128 + 1 × 64 + 1 × 32 + 0 × 16 + 0 × 8 + 1 × 4 + 1 × 2 + 1 × 1 = 871
Octal
1 5 4 7
1 × 512 + 5 × 64 + 4 × 8 + 7 × 1 = 871
Hexadecimal
3 6 7
3 × 256 + 6 × 16 + 7 × 1 = 871
Read as powers of two: 512 + 256 + 64 + 32 + 4 + 2 + 1 = 871.
In historical numeral systems
Egyptian
8 coils of rope, 7 hobbles, 1 stroke
8 × 100 + 7 × 10 + 1 × 1 = 871. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
1 corner wedge + 4 vertical wedges (sixties place), 3 corner wedges + 1 vertical wedge (units place)
14 × 60 + 31 = 871. Places are separated by a space on the tablet, with the higher place written first.
Greek (Ionic)
omega, then omicron, then alpha, marked as a numeral
omega-omicron-alpha + keraia
omega + omicron + alpha written in descending order and added — the letters carry their values wherever they stand, so this is addition, not place value.
Hebrew numerals
tav, then tav, then ayin, then alef
tav-tav-ayin-alef
tav (400) + tav (400) + ayin (70) + alef (1) = 871, written in descending order.
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
Alfred defended Wessex from 871 and Cnut ruled all England from 1016. The intervening period is the consolidation of a single English kingdom under pressure from the same direction.
View 1016 →Other connections
- is associated with1016
why?
Strength 0.50, confidence "high".
History
Alfred's reputation rests on fortified towns, a written law code and translating Latin works into English — state-building rather than victories, several of which he lost.
DocumentedHistoryGeography: EnglandPeriod: 871–899
Common questions
Is 871 a prime number?
No, 871 is not prime.
What are the factors of 871?
The factors of 871 are 1, 13, 67, 871.
What is 871 in Roman numerals?
871 in Roman numerals is DCCCLXXI.
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