150
Earth orbits about 150 million km from the Sun.
- Even
- Composite
Where 150 fits
Why 150 is special
That distance is the astronomical unit, and light takes about eight minutes and twenty seconds to cross it. Every image of the Sun shows it as it was eight minutes ago, which is the closest thing to a routine demonstration that light takes time.
Same number, different meanings
How 150 is understood across different contexts — never implying one meaning because of another.
- Mathematics
That distance is the astronomical unit, and light takes about eight minutes and twenty seconds to cross it. Every image of the Sun shows it as it was eight minutes ago, which is the closest thing to a routine demonstration that light takes time.
- Everyday life
E150 covers four classes of caramel colour produced by different processes. Class III and IV production yields 4-methylimidazole, which has attracted regulatory limits in some jurisdictions.
- Science
The suggested cognitive limit on stable social relationships is 150 (Dunbar's proposal, debated). Popularly called the number of friends a person can have, which is looser than the claim: Dunbar's category is people whose relationship to you and to each other you can track, not people you like. He derived it from primate neocortex ratios, the figure is widely cited, and the precise number remains contested.
150 is part of
Factors & digit properties
- Divisors (12)
- 1, 2, 3, 5, 6, 10, 15, 25, 30, 50, 75, 150
- Prime factorisation
- 2 × 3 × 5^2
- Digit sum
- 6
- Digital root
- 6
Representations
- Decimal
- 150
- Scientific notation
- 1.500 × 10^2
Roman numerals
C L
Binary
1 0 0 1 0 1 1 0
1 × 128 + 0 × 64 + 0 × 32 + 1 × 16 + 0 × 8 + 1 × 4 + 1 × 2 + 0 × 1 = 150
Octal
2 2 6
2 × 64 + 2 × 8 + 6 × 1 = 150
Hexadecimal
9 6
9 × 16 + 6 × 1 = 150
Read as powers of two: 128 + 16 + 4 + 2 = 150.
In historical numeral systems
Egyptian
1 coil of rope, 5 hobbles
1 × 100 + 5 × 10 = 150. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
2 vertical wedges (sixties place), 3 corner wedges (units place)
2 × 60 + 30 = 150. Places are separated by a space on the tablet, with the higher place written first.
Greek (Ionic)
rho, then nu, marked as a numeral
rho-nu + keraia
rho + nu written in descending order and added — the letters carry their values wherever they stand, so this is addition, not place value.
Hebrew numerals
qof, then nun
qof-nun
qof (100) + nun (50) = 150, written in descending order.
Maya
1 bar + 2 dots (upper, twenties place) over 2 bars (lower, units place)
7 × 20 + 10 = 150. 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
- Abundant number
- Harshad (Niven) number
Related numbers & connections
Mars orbits at about 228 million km against Earth's 150. Because both move, the distance between them ranges from about 55 to 400 million km, which is why launch windows open only every 26 months.
View 228 →150 appears in Numbers and memory, the topic covering numbers that carry a documented cognitive-science fact.
The Sun is about 390 times further away than the Moon and about 400 times wider, which is why the two appear almost the same size and why total eclipses work.
View 384400 →Mathematically related
- has multiple228
why?
Strength 0.50, confidence "high".
Numbers Around Us
- appears inHow people handle numbers
why?
Strength 0.50, confidence "high".
- appears inLiving things
why?
Strength 0.50, confidence "high".
Other connections
- is associated with384400
why?
Strength 0.50, confidence "high".
Everyday life
E150 covers four classes of caramel colour produced by different processes. Class III and IV production yields 4-methylimidazole, which has attracted regulatory limits in some jurisdictions.
DocumentedEveryday lifeGeography: European Union and states adopting the E number systemPeriod: 1962–
Science
The suggested cognitive limit on stable social relationships is 150 (Dunbar's proposal, debated). Popularly called the number of friends a person can have, which is looser than the claim: Dunbar's category is people whose relationship to you and to each other you can track, not people you like. He derived it from primate neocortex ratios, the figure is widely cited, and the precise number remains contested.
DocumentedScienceGeography: Dunbar's proposal, debatedThere are about 150 billion base pairs in the genome of the plant Paris japonica (worldwide, the largest genome yet measured). Fifty times the human genome, in a small white woodland flower. Genome size turns out to say almost nothing about complexity.
DocumentedScienceGeography: worldwide, the largest genome yet measuredThe mass of an adult blue whale is about 150 thousand kilograms. The largest animal known to have lived, heavier than any dinosaur yet found.
DocumentedScienceGeography: worldwideThe Sun is roughly 150 million km away, so sunlight left it about eight minutes before reaching your eye. If the Sun ceased to exist, Earth would continue in an ordinary orbit under ordinary daylight for those eight minutes.
DocumentedScience
Common questions
Is 150 a prime number?
No, 150 is not prime.
What are the factors of 150?
The factors of 150 are 1, 2, 3, 5, 6, 10, 15, 25, 30, 50, 75, 150.
What is 150 in Roman numerals?
150 in Roman numerals is CL.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 5 reviewer-confirmed records, sourced and reviewed before publication.
Last reviewed: 15 July 2026