Is 1621 a prime number?

The number 1621 has exactly 2 factors, 1 and 1621, which can divide the number completely without leaving any remainder. Thus, 1621 is classified as a prime number.

A number is considered prime if it has only two factors: 1 and the number itself. Since 1621 meets this criterion, it is a prime number.

Below are some commonly used methods to verify if a number is prime or composite.

Methods to check if a number is a prime number:

1. Counting Divisors Method
2. Divisibility Test
3. Prime Number Chart
4. Prime Factorization

In this method, we count the total divisors of the number.

For 1621:

Divisors of 1621 = 1, 1621
Number of divisors = 2

Since 1621, there have been only 2 divisors, which is a prime number.

Here, the number is tested for divisibility by smaller prime numbers (like 2, 3, 5, 7, etc.).

1621 is not divisible by any smaller prime number, confirming it has no divisors other than 1 and itself.
Thus, 1621 qualifies as a prime number.

A prime number chart lists all prime numbers starting from 2 onward.

The list of prime numbers from 1600 to 1700 are:
1601, 1607, 1609, 1613, 1619, 1621, 1627, 1637, 1657, 1663, 1667, 1669, 1693, 1697, 1699

Since 1621 is present in this list, it is a prime number.

Prime Number: A natural number greater than 1 that has exactly two distinct positive divisors: 1 and itself. For example, 1621 is a prime number.

Divisors: Numbers that divide another number completely without leaving a remainder. For instance, the divisors of 1621 are 1 and 1621.

Composite Number: A natural number greater than 1 that has more than two distinct positive divisors. For example, 12 is a composite number because it has divisors 1, 2, 3, 4, 6, and 12.

Prime Factorization: Expressing a number as a product of its prime factors. For a prime number like 1621, the factorization is simply 1621 × 1.

Divisibility Test: A method to determine if one number can divide another number without leaving a remainder.