# What is the composite number after 21?

## What is the composite number after 21?

4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 26, 27, 28, 30, 32, 33, 34, 35, 36, 38, 39, 40, 42, 44, 45, 46, 48, 49, 50.

### Is number 21 a prime?

A prime number is a whole number greater than 1 whose only factors are 1 and itself. A factor is a whole number that can be divided evenly into another number. The first few prime numbers are 2, 3, 5, 7, 11, 13, 17, 19, 23 and 29. Numbers that have more than two factors are called composite numbers.

#### Is 21 composite or prime?

Is 21 a Composite Number? Yes, since 21 has more than two factors i.e. 1, 3, 7, 21. In other words, 21 is a composite number because 21 has more than 2 factors.

Is 17 prime or composite?

There are 8 prime numbers under 20: 2, 3, 5, 7, 11, 13, 17 and 19. The first 10 prime numbers are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29. There are 25 prime numbers between 1 and 100.

Is 21 a good luck number?

What are the luckiest numbers? According to superstition, the five luckiest numbers are 3, 4, 8, 9, 12, 21 and 77. However, these numbers may not be considered lucky by all cultures.

## Is 21 a prime or composite number?

Yes, since 21 has more than two factors i.e. 1, 3, 7, 21. In other words, 21 is a composite number because 21 has more than 2 factors.

### Why is 21 a special number?

1 21 in Roman numerals is XXI. 2 21 is a triangle number – it is the sum of the first six whole numbers (1+2+3+4+5+6=21). 3 21 is the eighth number in the Fibonacci sequence, where each number is the sum of the two preceding ones. 5 21 is the atomic number of the chemical element scandium.

#### Why is 21 prime or composite?

Are 17 and 51 prime numbers?

Yes, 17 is a prime number because it only has two factors, 1 and 17. Is 51 a prime number? No, 51 is NOT a prime number because it has more than two factors. 51 is a composite number and can be factored by any of the following numbers: 1, 3, 17, 51.

Which number is the luckiest?

Why ‘7’ is the luckiest number.

## Is 25 prime or composite?

Yes, since 25 has more than two factors i.e. 1, 5, 25. In other words, 25 is a composite number because 25 has more than 2 factors. Problem Statements: Is 25 a Prime Number?

### What is 21st birthday called?

The 21st birthday, often called ‘coming of age’, once had special significance. In the early 2000s the legal age of majority was 20, but the 21st birthday was still seen by many as the threshold of adulthood.