828
The Burj Khalifa is 828 metres tall.
- Even
- Composite
Where 828 fits
Why 828 is special
It has held the record for tallest structure since 2010, an unusually long tenure — the title changed hands eleven times in the preceding century. Its buttressed core design is what let it exceed previous heights by a margin rather than incrementally.
828 is part of
Factors & digit properties
- Divisors (18)
- 1, 2, 3, 4, 6, 9, 12, 18, 23, 36, 46, 69, 92, 138, 207, 276, 414, 828
- Prime factorisation
- 2^2 × 3^2 × 23
- Digit sum
- 18
- Digital root
- 9
Representations
- Decimal
- 828
- Scientific notation
- 8.280 × 10^2
Roman numerals
D C C C X X V I I I
Binary
1 1 0 0 1 1 1 1 0 0
1 × 512 + 1 × 256 + 0 × 128 + 0 × 64 + 1 × 32 + 1 × 16 + 1 × 8 + 1 × 4 + 0 × 2 + 0 × 1 = 828
Octal
1 4 7 4
1 × 512 + 4 × 64 + 7 × 8 + 4 × 1 = 828
Hexadecimal
3 3 c
3 × 256 + 3 × 16 + c × 1 = 828
Read as powers of two: 512 + 256 + 32 + 16 + 8 + 4 = 828.
In historical numeral systems
Egyptian
8 coils of rope, 2 hobbles, 8 strokes
8 × 100 + 2 × 10 + 8 × 1 = 828. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
1 corner wedge + 3 vertical wedges (sixties place), 4 corner wedges + 8 vertical wedges (units place)
13 × 60 + 48 = 828. Places are separated by a space on the tablet, with the higher place written first.
Greek (Ionic)
omega, then kappa, then eta, marked as a numeral
omega-kappa-eta + keraia
omega + kappa + eta 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 kaf, then het
tav-tav-kaf-het
tav (400) + tav (400) + kaf (20) + het (8) = 828, 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
- Palindromic number
- Abundant number
- Harshad (Niven) number
Related numbers & connections
The Petronas Towers took the height record in 1998 because spires count as architecture and antennas do not. The Burj Khalifa exceeded it by a margin large enough that the definition stopped mattering.
View 452 →Technology & computing
The Burj Khalifa has been the tallest structure since 2010. Height records changed roughly every decade through the twentieth century, so holding it for fifteen years reflects a genuine step change rather than a small increment.
DocumentedTechnology & computingGeography: Dubai, United Arab EmiratesPeriod: 2010
Common questions
Is 828 a prime number?
No, 828 is not prime.
What are the factors of 828?
The factors of 828 are 1, 2, 3, 4, 6, 9, 12, 18, 23, 36, 46, 69, 92, 138, 207, 276, 414, 828.
What is 828 in Roman numerals?
828 in Roman numerals is DCCCXXVIII.
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