253
+253 is the international calling code for Djibouti.
- Odd
- Composite
Where 253 fits
Why 253 is special
Djibouti is small and strategically placed at the mouth of the Red Sea, and hosts military bases from several countries simultaneously, including the United States and China.
Same number, different meanings
How 253 is understood across different contexts — never implying one meaning because of another.
- Mathematics
Djibouti is small and strategically placed at the mouth of the Red Sea, and hosts military bases from several countries simultaneously, including the United States and China.
- Science
NGC 253, the Sculptor Galaxy, is among the nearest starburst galaxies. Its proximity allows individual star-forming regions and a galactic wind to be resolved directly.
- Geography
+253 reaches Djibouti, which controls access to the Red Sea and hosts foreign military bases from multiple, occasionally rival, powers at the same time.
253 is part of
Factors & digit properties
- Divisors (4)
- 1, 11, 23, 253
- Prime factorisation
- 11 × 23
- Digit sum
- 10
- Digital root
- 1
Representations
- Decimal
- 253
- Scientific notation
- 2.530 × 10^2
Roman numerals
C C L I I I
Binary
1 1 1 1 1 1 0 1
1 × 128 + 1 × 64 + 1 × 32 + 1 × 16 + 1 × 8 + 1 × 4 + 0 × 2 + 1 × 1 = 253
Octal
3 7 5
3 × 64 + 7 × 8 + 5 × 1 = 253
Hexadecimal
f d
f × 16 + d × 1 = 253
Read as powers of two: 128 + 64 + 32 + 16 + 8 + 4 + 1 = 253.
In historical numeral systems
Egyptian
2 coils of rope, 5 hobbles, 3 strokes
2 × 100 + 5 × 10 + 3 × 1 = 253. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
4 vertical wedges (sixties place), 1 corner wedge + 3 vertical wedges (units place)
4 × 60 + 13 = 253. Places are separated by a space on the tablet, with the higher place written first.
Greek (Ionic)
sigma, then nu, then gamma, marked as a numeral
sigma-nu-gamma + keraia
sigma + nu + gamma written in descending order and added — the letters carry their values wherever they stand, so this is addition, not place value.
Hebrew numerals
resh, then nun, then gimel
resh-nun-gimel
resh (200) + nun (50) + gimel (3) = 253, written in descending order.
Maya
2 bars + 2 dots (upper, twenties place) over 2 bars + 3 dots (lower, units place)
12 × 20 + 13 = 253. Places stack vertically with the smallest at the bottom, so the upper group is worth twenty times the lower.
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
- Triangular number
- Deficient number
- Semiprime
Related numbers & connections
Somalia and Djibouti sit at the mouth of the Red Sea. Djibouti hosts military bases from several rival powers simultaneously.
View 252 →Nearby in a sequence
- is adjacent to252
why?
Strength 0.50, confidence "high".
Science
NGC 253, the Sculptor Galaxy, is among the nearest starburst galaxies. Its proximity allows individual star-forming regions and a galactic wind to be resolved directly.
DocumentedSciencePeriod: 1783–
Geography
+253 reaches Djibouti, which controls access to the Red Sea and hosts foreign military bases from multiple, occasionally rival, powers at the same time.
DocumentedGeographyGeography: Djibouti
Common questions
Is 253 a prime number?
No, 253 is not prime.
What are the factors of 253?
The factors of 253 are 1, 11, 23, 253.
What is 253 in Roman numerals?
253 in Roman numerals is CCLIII.
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