Prime numbers between 1 and 10
There are 4 prime numbers between 1 and 10: 2, 3, 5, 7.
How to work it out
- 1
A prime has exactly two factors, 1 and itself. To list them, cross out multiples of 2, then 3, then 5, and so on up to ā10 ā 3.2 (the sieve of Eratosthenes). What is left are the primes.
- 2
That leaves 4 primes between 1 and 10, with a total of 17.
- 3
The biggest gap between neighbouring primes in this range is 2, after 3 (the next prime is 5). There are 2 twin prime pairs (primes 2 apart): (3, 5), (5, 7).
How many primes in each part
| Range | Primes | Share of the numbers |
|---|---|---|
| 1 to 10 | 4 | 40% |
Questions
How many prime numbers are there between 1 and 10?
4.
What is the biggest prime number below 10?
7.
What is the first prime number after 0?
2.