129 in words
129
one hundred twenty-nine
129 is written one hundred twenty-nine.
Ways to write it
- As an ordinal
- one hundred twenty-ninth
- Roman numeral
- CXXIX
- Expanded form
- 100 + 20 + 9
Place value
| Place | Digit | Value |
|---|---|---|
| hundreds | 1 | 100 |
| tens | 2 | 20 |
| ones | 9 | 9 |
Number facts
- Even or odd
- Odd
- Prime or composite
- Composite
- Factors
- 1, 3, 43 and 129 (4 factors)
- First 10 multiples
- 129, 258, 387, 516, 645, 774, 903, 1,032, 1,161, 1,290
- Square
- 129 × 129 = 16,641
- Square root
- ≈ 11.36
- Sum of the digits
- 1 + 2 + 9 = 12
- Rounded to the nearest 10
- 130
- Rounded to the nearest 100
- 100
- Number before
- 128
- Number after
- 130
- In binary
10000001
Quick check
What number comes just after 129?
Show the answer
130
Is 129 even or odd?
Show the answer
Odd
What is 129 + 10?
Show the answer
139
Practise with a game
Times Tables Challenge
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Factors, Multiples & Primes
Multiples, factors, prime numbers, square numbers and prime factors.Frequently asked questions
How do you write 129 in words?
129 is written "one hundred twenty-nine".
Is 129 a prime number?
No. 129 is a composite number, because it has more than two factors.
What are the factors of 129?
The factors of 129 are 1, 3, 43 and 129.
How do you write 129 in Roman numerals?
129 in Roman numerals is CXXIX.