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Country and language

Country and language: Singapore

Country and language

1 in words

1

one

1 is written one.

Ways to write it

As an ordinal
first
Roman numeral
I

Place value

PlaceDigitValue
ones11

Number facts

Even or odd
Odd
Prime or composite
Neither prime nor composite
Factors
1 (1 factor)
First 10 multiples
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
Square
1 × 1 = 1
Square root
1
Rounded to the nearest 10
0
Number before
0
Number after
2
In binary
1

Quick check

  1. What number comes just after 1?

    Show the answer

    2

  2. Is 1 even or odd?

    Show the answer

    Odd

  3. What is 1 + 10?

    Show the answer

    11

Practise with a game

Count with Me

Count pictures up to 5, 10 or 20 and compare groups.

Frequently asked questions

How do you write 1 in words?

1 is written "one".

Is 1 a prime number?

No. 1 is neither prime nor composite.

What are the factors of 1?

The factors of 1 are 1.

How do you write 1 in Roman numerals?

1 in Roman numerals is I.