1428
1428 is the year the Aztec Triple Alliance was formed.
- Even
- Composite
Where 1428 fits
Why 1428 is special
Three city-states allied and dominated central Mexico for ninety years. The empire Cortés encountered was less than a century old.
Factors & digit properties
- Divisors (24)
- 1, 2, 3, 4, 6, 7, 12, 14, 17, 21, 28, 34, 42, 51, 68, 84, 102, 119, 204, 238, 357, 476, 714, 1428
- Prime factorisation
- 2^2 × 3 × 7 × 17
- Digit sum
- 15
- Digital root
- 6
Representations
- Decimal
- 1428
- Binary
- 10110010100
- Octal
- 2624
- Hexadecimal
- 594
- Roman numeral
- MCDXXVIII
- Scientific notation
- 1.428 × 10^3
Other mathematical patterns
- Abundant number
Related numbers & connections
The Aztec Triple Alliance formed in 1428 and Pizarro captured the Inca emperor in 1532. Both empires the Spanish encountered were recent, and both fell to disease as much as to conquest.
View 1532 →Other connections
- is associated with1532
why?
Strength 0.50, confidence "high".
History
The Aztec empire dates from a 1428 alliance of three city-states, so it was roughly ninety years old when the Spanish arrived. Its recent formation is part of why subject peoples allied against it.
DocumentedHistoryGeography: MexicoPeriod: 1428
Common questions
Is 1428 a prime number?
No, 1428 is not prime.
What are the factors of 1428?
The factors of 1428 are 1, 2, 3, 4, 6, 7, 12, 14, 17, 21, 28, 34, 42, 51, 68, 84, 102, 119, 204, 238, 357, 476, 714, 1428.
What is 1428 in Roman numerals?
1428 in Roman numerals is MCDXXVIII.
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: 3 August 2026