1202
1202 is the alarm code that nearly aborted the first Moon landing.
- Even
- Composite
Where 1202 fits
Why 1202 is special
The guidance computer signalled 1202 during descent because it was being given more work than it could complete. It had been designed to shed low-priority tasks and keep flying, and a 26-year-old engineer who knew that recognised the alarm as survivable within seconds. The landing continued.
Same number, different meanings
How 1202 is understood across different contexts — never implying one meaning because of another.
- Mathematics
The guidance computer signalled 1202 during descent because it was being given more work than it could complete. It had been designed to shed low-priority tasks and keep flying, and a 26-year-old engineer who knew that recognised the alarm as survivable within seconds. The landing continued.
- History
In 1202, Leonardo of Pisa's Liber Abaci introduced Hindu-Arabic numerals and positional notation to Latin Europe (Italy).
- Technology & computing
The Apollo 11 guidance computer raised 1202 during descent because it was receiving more work than it could finish. It had been written to discard low-priority tasks and keep the essential loop running, and the engineer who knew that said so within seconds. Had the design been to halt on overload, the landing would have been aborted.
1202 is part of
Factors & digit properties
- Divisors (4)
- 1, 2, 601, 1202
- Prime factorisation
- 2 × 601
- Digit sum
- 5
- Digital root
- 5
Representations
- Decimal
- 1202
- Scientific notation
- 1.202 × 10^3
Roman numerals
M C C I I
Binary
1 0 0 1 0 1 1 0 0 1 0
1 × 1,024 + 0 × 512 + 0 × 256 + 1 × 128 + 0 × 64 + 1 × 32 + 1 × 16 + 0 × 8 + 0 × 4 + 1 × 2 + 0 × 1 = 1,202
Octal
2 2 6 2
2 × 512 + 2 × 64 + 6 × 8 + 2 × 1 = 1,202
Hexadecimal
4 b 2
4 × 256 + b × 16 + 2 × 1 = 1,202
Read as powers of two: 1,024 + 128 + 32 + 16 + 2 = 1,202.
In historical numeral systems
Egyptian
1 lotus, 2 coils of rope, 2 strokes
1 × 1,000 + 2 × 100 + 2 × 1 = 1,202. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
2 corner wedges (sixties place), 2 vertical wedges (units place)
20 × 60 + 2 = 1202. 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
- Semiprime
Related numbers & connections
1202 is a year in the 13th century, in the 1200s.
The Apollo guidance computer raised alarm 1202 during the 1969 descent because it was overloaded, and kept flying because it had been written to shed low-priority work.
View 1969 →Numbers Around Us
- appears inHistorical years
why?
Strength 0.50, confidence "high".
Other connections
- is associated with1969
why?
Strength 0.50, confidence "high".
History
In 1202, Leonardo of Pisa's Liber Abaci introduced Hindu-Arabic numerals and positional notation to Latin Europe (Italy).
DocumentedHistoryGeography: ItalyPeriod: 1202
Technology & computing
The Apollo 11 guidance computer raised 1202 during descent because it was receiving more work than it could finish. It had been written to discard low-priority tasks and keep the essential loop running, and the engineer who knew that said so within seconds. Had the design been to halt on overload, the landing would have been aborted.
DocumentedTechnology & computingPeriod: 20 July 1969
Common questions
Is 1202 a prime number?
No, 1202 is not prime.
What are the factors of 1202?
The factors of 1202 are 1, 2, 601, 1202.
What is 1202 in Roman numerals?
1202 in Roman numerals is MCCII.
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