401 in words
401
four hundred and one
401 is written four hundred and one.
Ways to write it
- As an ordinal
- four hundred and first
- Roman numeral
- CDI
- Expanded form
- 400 + 1
Place value
| Place | Digit | Value |
|---|---|---|
| hundreds | 4 | 400 |
| tens | 0 | 0 |
| ones | 1 | 1 |
Number facts
- Even or odd
- Odd
- Prime or composite
- Prime
- Factors
- 1 and 401 (2 factors)
- First 10 multiples
- 401, 802, 1,203, 1,604, 2,005, 2,406, 2,807, 3,208, 3,609, 4,010
- Square
- 401 × 401 = 160,801
- Square root
- ≈ 20.02
- Sum of the digits
- 4 + 0 + 1 = 5
- Rounded to the nearest 10
- 400
- Rounded to the nearest 100
- 400
- Number before
- 400
- Number after
- 402
- In binary
110010001
Quick check
What number comes just after 401?
Show the answer
402
Is 401 even or odd?
Show the answer
Odd
What is 401 + 10?
Show the answer
411
Practise 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 401 in words?
401 is written "four hundred and one".
Is 401 a prime number?
Yes. 401 is a prime number: its only factors are 1 and 401.
What are the factors of 401?
The factors of 401 are 1 and 401.
How do you write 401 in Roman numerals?
401 in Roman numerals is CDI.