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Last updated on August 29, 2025
The natural numbers greater than 1 that are not divisible by any other numbers except 1 and themselves are called prime numbers. Prime numbers have exactly two distinct positive divisors: 1 and the number itself. Beyond mathematics, prime numbers are crucial in fields like cryptography, computer algorithms, and more. In this topic, we will explore the prime numbers from 1 to 120.
A prime number is a natural number that cannot be divided evenly by any other number except 1 and itself. Here are some fundamental properties of prime numbers:
Every number greater than 1 is divisible by at least one prime number.
Any two distinct prime numbers are always relatively prime to each other.
Every even positive integer greater than 2 can be expressed as the sum of two prime numbers (Goldbach's conjecture, which remains unproven).
Every composite number can be uniquely factored into prime factors.
Except for 2, all prime numbers are odd; 2 is the only even prime number.
A prime number chart displays prime numbers in ascending order up to a specified limit, making it easier to identify prime numbers within a range.
A prime number chart helps in foundational mathematics and the fundamental theorem of arithmetic.
The list of all prime numbers from 1 to 120 provides a comprehensive view of numbers in this range that can only be divided by 1 and the number itself. The prime numbers in the range of 1 to 120 include:
Except for the number 2, all prime numbers are odd because they cannot be evenly divided by 2. Hence, aside from 2, all prime numbers are considered a subset of odd numbers.
Prime numbers are natural numbers greater than 1 that are only divisible by 1 and themselves. Here are two methods to determine if a number is prime:
Divisibility Method:
To determine if a number is prime, check its divisibility. If a number is divisible by any prime number up to its square root, it is not prime. For example: To check if 47 is a prime number,
47 ÷ 2 = 23.5 (remainder ≠ 0)
47 ÷ 3 = 15.67 (remainder ≠ 0)
47 ÷ 5 = 9.4 (remainder ≠ 0)
Since no divisors are found, 47 is a prime number.
Prime Factorization Method:
This method involves breaking down a composite number into its prime factors, demonstrating that it is not prime. This method helps identify prime numbers up to 120 by using the smallest prime building blocks.
Rule 1: Divisibility Check:
Prime numbers are natural numbers greater than 1 with no divisors other than 1 and the number itself. In this rule, we check divisibility by small prime numbers. If divisible, it is not prime.
Rule 2: Prime Factorization:
Break down numbers into their prime factors, showing them as products of prime numbers.
Rule 3: Sieve of Eratosthenes Method:
An ancient algorithm to find all prime numbers up to a limit. List numbers from 1 to 120, start with 2, and mark all multiples of 2 as non-prime. Repeat with the next unmarked number, continuing to numbers up to the square root of 120 (approximately 10.95). The unmarked numbers are prime.
Tips and Tricks for Prime Numbers 1 to 120
Memorize small prime numbers like 2, 3, 5, 7, 11, and 13 for quick reference.
Practice using the Sieve of Eratosthenes method effectively.
Understand that numbers like 4, 8, 9, 16, and 25 are not prime.
Recognizing common squares helps avoid unnecessary checks.
When working with prime numbers 1 to 120, students may encounter errors. Here are some solutions:
Is 113 a prime number?
Yes, 113 is a prime number.
The square root of 113 is approximately 10.63.
Check divisibility by primes less than 10.63
(2, 3, 5, 7).
113 ÷ 2 = 56.5
113 ÷ 3 = 37.67
113 ÷ 5 = 22.6
113 ÷ 7 = 16.14
Since 113 is not divisible by any of these numbers, it is a prime number.
Sophie wants to set a lock with a 3-digit code. The code is the largest prime number under 120. What number will she use?
113 is the 3-digit code for the lock and the largest prime number under 120.
Prime numbers are natural numbers greater than 1 with no divisors other than 1 and the number itself.
The prime numbers under 120 include 2, 3, 5, 7, 11, 13, and so on.
113 is the largest prime number under 120, so the code for the lock is 113.
A teacher asks students to find the prime numbers closest to 50 but less than 50.
47 is the prime number closest to 50.
47 is a prime number because it is only divisible by 1 and itself.
The next prime number after 47 is 53, which is greater than 50.
Thus, the prime number closest to and less than 50 is 47.
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.