# Is 45 a Prime Number?

Is 45 a prime number? * "No, 45 is not a prime number."* A number can be classified as prime or composite depending on the factors it contains; it could either have only 2 factors or more than 2 factors. Numbers like 631 with only 2 factors, i.e. 1 and 631 are called prime numbers. However, numbers like 436 with more than 2 factors are called composite numbers. Let us find out how and why is 45 a prime number or a composite number?

**Is 45 a prime number? -**No**Is 45 a composite number? -**Yes**Is 45 a perfect square? -**No**Factors of 45 -**1, 3, 5, 9, 15, 45**Prime Factors of 45 -**3, 5

## Is 45 a Prime Number?

No, 45 is not a prime number. The number 45 is divisible by 1, 3, 5, 9, 15, 45. For a number to be classified as a prime number, it should have exactly two factors. Since 45 has more than two factors, i.e. 1, 3, 5, 9, 15, 45, it is not a prime number.

## Why is 45 not a Prime Number?

To understand whether 45 is composite or prime, it is important to find its factors.

**Factors of 45:** 1, 3, 5, 9, 15, 45

Since 45 has more than 2 factors, we can say that 45 is not a prime number.

## Is 45 a Composite Number?

Yes, since 45 has more than two factors i.e. 1, 3, 5, 9, 15, 45. In other words, 45 is a composite number because 45 has more than 2 factors.

**Problem Statements: **

Is 45 a Prime Number? | No |

Is 45 a Composite Number? | Yes |

Multiples of 45 | 45, 90, 135, 180, 225, 270, 315, 360, 405, 450 |

Is 45 a Perfect Cube? | No |

Square Root of 45 | 6.708204 |

Is 45 an Odd Number? | Yes |

Cube Root of 45 | 3.556889 |

Is 45 a Perfect Square? | No |

Is 45 an Even Number? | No |

Square of 45 | 2025 |

**Fun Facts: **

- Prime numbers greater than 5 can be represented in the form of either 6n + 1 or 6n - 1. Example - 71 is a prime number and it can be written as 71 = 6 × 12 - 1
- Euler discovered a polynomial n
^{2}+ n + 41 that produces prime numbers for values of n that lie between 0 and 39 inclusive. It can generate 40 prime numbers for 0 <= n <= 39. - A semiprime number is a composite number that is the product of exactly two prime numbers. Example - 115 is semiprime, since 115 can be written as 5 × 23.

**☛ Also Check: **

- Is 9 a Prime Number? - No
- Is 27 a Prime Number? - No
- Is 14 a Prime Number? - No
- Is 289 a Prime Number? - No
- Is 73 a Prime Number? - Yes
- Is 82 a Prime Number? - No
- Is 899 a Prime Number? - No
- Is 118 a Prime Number? - No

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