1721
1721 is the year Britain acquired its first de facto prime minister.
- Odd
- Prime
Where 1721 fits
Why 1721 is special
Robert Walpole held office for over twenty years without the title, which was informal and initially an insult. The role of prime minister has never been created by statute and rests on convention to this day.
Same number, different meanings
How 1721 is understood across different contexts — never implying one meaning because of another.
- Mathematics
Robert Walpole held office for over twenty years without the title, which was informal and initially an insult. The role of prime minister has never been created by statute and rests on convention to this day.
- History
In 1721, Robert Walpole became in effect Britain's first prime minister (Britain).
- Law & regulation
There is no statute establishing the office of British prime minister. Walpole's long dominance from 1721 created the role by practice, and it still rests on convention rather than law — which is why its powers are so hard to state precisely.
1721 is part of
Factors & digit properties
- Divisors (2)
- 1, 1721
- Prime factorisation
- 1721
- Digit sum
- 11
- Digital root
- 2
Representations
- Decimal
- 1721
- Scientific notation
- 1.721 × 10^3
Roman numerals
M D C C X X I
Binary
1 1 0 1 0 1 1 1 0 0 1
1 × 1,024 + 1 × 512 + 0 × 256 + 1 × 128 + 0 × 64 + 1 × 32 + 1 × 16 + 1 × 8 + 0 × 4 + 0 × 2 + 1 × 1 = 1,721
Octal
3 2 7 1
3 × 512 + 2 × 64 + 7 × 8 + 1 × 1 = 1,721
Hexadecimal
6 b 9
6 × 256 + b × 16 + 9 × 1 = 1,721
Read as powers of two: 1,024 + 512 + 128 + 32 + 16 + 8 + 1 = 1,721.
In historical numeral systems
Egyptian
1 lotus, 7 coils of rope, 2 hobbles, 1 stroke
1 × 1,000 + 7 × 100 + 2 × 10 + 1 × 1 = 1,721. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
2 corner wedges + 8 vertical wedges (sixties place), 4 corner wedges + 1 vertical wedge (units place)
28 × 60 + 41 = 1721. 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
- Twin prime
Related numbers & connections
1721 is a year in the 18th century, in the 1720s.
Peter the Great toured western Europe in disguise in 1697, and the reforms that followed reoriented Russia by force. Britain acquired its first de facto prime minister in 1721 by a quieter route.
View 1697 →Numbers Around Us
- appears inHistorical years
why?
Strength 0.50, confidence "high".
Other connections
- is associated with1697
why?
Strength 0.50, confidence "high".
History
In 1721, Robert Walpole became in effect Britain's first prime minister (Britain).
DocumentedHistoryGeography: BritainPeriod: 1721
Law & regulation
There is no statute establishing the office of British prime minister. Walpole's long dominance from 1721 created the role by practice, and it still rests on convention rather than law — which is why its powers are so hard to state precisely.
DocumentedLaw & regulationGeography: Great BritainPeriod: 1721
Common questions
Is 1721 a prime number?
Yes, 1721 is prime — it has exactly two positive divisors: 1 and itself.
What are the factors of 1721?
The factors of 1721 are 1, 1721.
What is 1721 in Roman numerals?
1721 in Roman numerals is MDCCXXI.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 2 reviewer-confirmed records, sourced and reviewed before publication.
Last reviewed: 15 July 2026