161 in words
161
one hundred sixty-one
161 is written one hundred sixty-one.
Ways to write it
- As an ordinal
- one hundred sixty-first
- Roman numeral
- CLXI
- Expanded form
- 100 + 60 + 1
Place value
| Place | Digit | Value |
|---|---|---|
| hundreds | 1 | 100 |
| tens | 6 | 60 |
| ones | 1 | 1 |
Number facts
- Even or odd
- Odd
- Prime or composite
- Composite
- Factors
- 1, 7, 23 and 161 (4 factors)
- First 10 multiples
- 161, 322, 483, 644, 805, 966, 1,127, 1,288, 1,449, 1,610
- Square
- 161 × 161 = 25,921
- Square root
- ≈ 12.69
- Sum of the digits
- 1 + 6 + 1 = 8
- Rounded to the nearest 10
- 160
- Rounded to the nearest 100
- 200
- Number before
- 160
- Number after
- 162
- In binary
10100001
Quick check
What number comes just after 161?
Show the answer
162
Is 161 even or odd?
Show the answer
Odd
What is 161 + 10?
Show the answer
171
Practice with a game
Factors, Multiples & Primes
Multiples, factors, prime numbers, square numbers and prime factors.
Roman Numerals
Read and write Roman numerals from I to 3,999.Frequently asked questions
How do you write 161 in words?
161 is written "one hundred sixty-one".
Is 161 a prime number?
No. 161 is a composite number, because it has more than two factors.
What are the factors of 161?
The factors of 161 are 1, 7, 23 and 161.
How do you write 161 in Roman numerals?
161 in Roman numerals is CLXI.