# Is 561 a Prime Number?

Is 561 a prime number? * "No, 561 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 31 with only 2 factors, i.e. 1 and 31 are called prime numbers. However, numbers like 462 with more than 2 factors are called composite numbers. Let us find out how and why is 561 a prime number or a composite number?

**Is 561 a prime number? -**No**Is 561 a composite number? -**Yes**Is 561 a perfect square? -**No**Factors of 561 -**1, 3, 11, 17, 33, 51, 187, 561**Prime Factors of 561 -**3, 11, 17

## Is 561 a Prime Number?

No, 561 is not a prime number. The number 561 is divisible by 1, 3, 11, 17, 33, 51, 187, 561. For a number to be classified as a prime number, it should have exactly two factors. Since 561 has more than two factors, i.e. 1, 3, 11, 17, 33, 51, 187, 561, it is not a prime number.

## Why is 561 not a Prime Number?

To understand whether 561 is prime or composite, it is important to find its factors.

**Factors of 561:** 1, 3, 11, 17, 33, 51, 187, 561

Since 561 has more than 2 factors, we can say that 561 is not a prime number.

## Is 561 a Composite Number?

Yes, since 561 has more than two factors i.e. 1, 3, 11, 17, 33, 51, 187, 561. In other words, 561 is a composite number because 561 has more than 2 factors.

**Problem Statements: **

Is 561 a Prime Number? | No |

Is 561 a Composite Number? | Yes |

Is 561 a Perfect Square? | No |

Square of 561 | 314721 |

Cube Root of 561 | 8.247457 |

Is 561 an Even Number? | No |

Square Root of 561 | 23.685439 |

Is 561 an Odd Number? | Yes |

Multiples of 561 | 561, 1122, 1683, 2244, 2805, 3366, 3927, 4488, 5049, 5610 |

Is 561 a Perfect Cube? | No |

**Fun Facts: **

- 23 is the smallest prime number having consecutive digits.
- 5 is the only prime number having the last digit as 5.
- A palindrome prime is a prime number that when read in reverse order results in the same number. Examples - 10601, 11311, 12421

**☛ Also Check: **

- Is 34 a Prime Number? - No
- Is 97 a Prime Number? - Yes
- Is 147 a Prime Number? - No
- Is 71 a Prime Number? - Yes
- Is 221 a Prime Number? - No
- Is 571 a Prime Number? - Yes
- Is 163 a Prime Number? - Yes
- Is 215 a Prime Number? - No

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