1421
1421 is the year Beijing became the capital of China.
- Odd
- Composite
Where 1421 fits
Why 1421 is special
The Yongle Emperor moved the capital north and built the Forbidden City, which took a million workers and remained the imperial seat for five centuries.
1421 is part of
Factors & digit properties
- Divisors (6)
- 1, 7, 29, 49, 203, 1421
- Prime factorisation
- 7^2 × 29
- Digit sum
- 8
- Digital root
- 8
Representations
- Decimal
- 1421
- Scientific notation
- 1.421 × 10^3
Roman numerals
M C D X X I
MCDXXI uses the subtractive pair CD: a hundred before five hundred — five hundred minus a hundred.
Binary
1 0 1 1 0 0 0 1 1 0 1
1 × 1,024 + 0 × 512 + 1 × 256 + 1 × 128 + 0 × 64 + 0 × 32 + 0 × 16 + 1 × 8 + 1 × 4 + 0 × 2 + 1 × 1 = 1,421
Octal
2 6 1 5
2 × 512 + 6 × 64 + 1 × 8 + 5 × 1 = 1,421
Hexadecimal
5 8 d
5 × 256 + 8 × 16 + d × 1 = 1,421
Read as powers of two: 1,024 + 256 + 128 + 8 + 4 + 1 = 1,421.
In historical numeral systems
Egyptian
1 lotus, 4 coils of rope, 2 hobbles, 1 stroke
1 × 1,000 + 4 × 100 + 2 × 10 + 1 × 1 = 1,421. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
2 corner wedges + 3 vertical wedges (sixties place), 4 corner wedges + 1 vertical wedge (units place)
23 × 60 + 41 = 1421. 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
Related numbers & connections
1421 is a year in the 15th century, in the 1420s.
Beijing became the capital in 1421 under the same emperor who sent Zheng He's treasure voyages from 1405. Both were assertions of Ming reach, and both were reversed by later policy.
View 1405 →Numbers Around Us
- appears inHistorical years
why?
Strength 0.50, confidence "high".
Other connections
- is associated with1405
why?
Strength 0.50, confidence "high".
History
In 1421, Beijing replaced Nanjing as the Ming capital (China).
DocumentedHistoryGeography: ChinaPeriod: 1421Yongle relocated the Chinese capital to Beijing in 1421 and constructed the Forbidden City for it. The complex served as the imperial seat until 1912.
DocumentedHistoryGeography: ChinaPeriod: 1421
Common questions
Is 1421 a prime number?
No, 1421 is not prime.
What are the factors of 1421?
The factors of 1421 are 1, 7, 29, 49, 203, 1421.
What is 1421 in Roman numerals?
1421 in Roman numerals is MCDXXI. CD is subtractive: a hundred before five hundred — five hundred minus a hundred. Written additively it would be MCCCCXXI, 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: 2 reviewer-confirmed records, sourced and reviewed before publication.
Last reviewed: 15 July 2026