1 in words

Ways to write it

As an ordinal

first

Roman numeral

I

Place value

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

Practice with a game

Count with Me

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

Place Value Quest

Ones, tens, hundreds and thousands.

Roman Numerals

Read and write Roman numerals from I to 3,999.

Frequently asked questions