Last updated on July 1st, 2025
Prime numbers are natural numbers greater than 1 that have no divisors other than 1 and the number itself. Prime numbers have only two factors: 1 and the number itself. Beyond mathematics, prime numbers are used in various fields, such as securing digital data and radio frequency identification. In this topic, we will learn about the prime numbers from 1 to 250.
A prime number is a natural number with no positive factors other than 1 and itself. A prime number can only be evenly divisible by 1 and itself. Here are some basic properties of prime numbers:
A prime number chart is a table showing the prime numbers in increasing order. The chart includes all the prime numbers up to a certain limit, helping to identify the prime numbers within a range.
For educational purposes, it is easier for children to understand prime numbers through a chart. The significance of this prime number chart is used in different fields like the foundation of mathematics and the fundamental theorem of arithmetic.
The list of all prime numbers from 1 to 250 provides a comprehensive view of numbers within this range that can only be divided by 1 and the number itself. The prime numbers in the range of 1 to 250 include:
Prime numbers and odd numbers are those only divisible by 1 and themselves. They cannot be evenly divisible by 2 or other numbers. 2 is the only even prime number, which divides all the non-prime numbers. Therefore, except for 2, all prime numbers are considered a set of odd numbers.
Prime numbers are natural numbers that can only be divided by 1 and themselves. Here are two important methods to determine whether a number is prime:
To determine whether a number is prime, use the divisibility method. If a number is divisible by 2, 3, or 5, it is not a prime number. Prime numbers are only divisible by 1 and themselves, so if a number is only divisible by 1 and itself, it is a prime number.
For example: To check whether 37 is a prime number:
Step 1: 37 ÷ 2 = 18.5 (remainder ≠ 0)
Step 2: 37 ÷ 3 = 12.33 (remainder ≠ 0)
Step 3: 37 ÷ 5 = 7.4 (remainder ≠ 0)
Since no divisors are found, 37 is a prime number.
The prime factorization method involves breaking down a composite number into the product of its prime factors. This method helps identify prime numbers up to 250 by breaking down numbers into their smallest prime factors. For example: Prime factorization of 250:
Step 1: 250 ÷ 2 = 125
Step 2: Now divide 125, 125 ÷ 5 = 25
Step 3: Take 25, since 25 ends in 5 divide the number with 5 25 ÷ 5 = 5
Step 4: At last, take 5. 5 ÷ 5 = 1 (since 5 is a prime number, and dividing by 5 gives 1)
Therefore, the prime factorization of 250 is: 250 = 2 × 5².
Rule 1: Divisibility Check: Prime numbers are natural numbers greater than 1 that have no divisors other than 1 and themselves. In the divisibility check rule, we check whether a number is divisible by 2, 3, 5, or 7. If it is divisible by any of these numbers, then it is not a prime number.
Rule 2: Prime Factorization: In this method, break down all numbers into their prime factors, representing them as the product of prime numbers.
Rule 3: Sieve of Eratosthenes Method: The Sieve of Eratosthenes is an ancient algorithm used to find all prime numbers up to a given limit. First, list all numbers from 1 to 250. Then start with the first prime number, 2, and mark all multiples of 2 as non-prime.
Repeat the process for the next unmarked prime number and continue until you reach the square root of 250, approximately 15.81. The remaining unmarked numbers are the prime numbers.
While working with prime numbers from 1 to 250, children might encounter some errors or difficulties. Here are some solutions to resolve those problems:
Is 241 a prime number?
Yes, 241 is a prime number.
The square root of 241 is √241 ≈ 15.52.
We check divisibility by primes less than 15.52 (2, 3, 5, 7, 11, 13).
241 ÷ 2 = 120.5
241 ÷ 3 = 80.33
241 ÷ 5 = 48.2
241 ÷ 7 = 34.42
241 ÷ 11 = 21.91
Since 241 is not divisible by any of these numbers, 241 is a prime number.
Sarah wants to find a prime number to use as a security code. What is the largest prime number under 250 that she can use?
The largest prime number under 250 is 241.
Prime numbers are natural numbers greater than 1 that have no divisors other than 1 and themselves. Under 250, the largest prime number is 241, making it the best choice for Sarah's security code.
A student is asked to find the prime number that is closest to 100 but less than 100. What is the number?
The prime number closest to 100 but less than 100 is 97.
97 is a prime number because it is only divisible by 1 and itself. The next prime number after 97 is 101, which is greater than 100. Therefore, the prime number closest to 100 and less than 100 is 97.
Hiralee Lalitkumar Makwana has almost two years of teaching experience. She is a number ninja as she loves numbers. Her interest in numbers can be seen in the way she cracks math puzzles and hidden patterns.
: She loves to read number jokes and games.