Is 406 a prime number? What are the divisors of 406?

## Is 406 a prime number?

It is possible to find out using mathematical methods whether a given integer is a prime number or not.

For 406, the answer is: No, 406 is not a prime number.

The list of all positive divisors (i.e., the list of all integers that divide 406) is as follows: 1, 2, 7, 14, 29, 58, 203, 406.

To be 406 a prime number, it would have been required that 406 has only two divisors, i.e., itself and 1.

As a consequence:

• 406 is a multiple of 1
• 406 is a multiple of 2
• 406 is a multiple of 7
• 406 is a multiple of 14
• 406 is a multiple of 29
• 406 is a multiple of 58
• 406 is a multiple of 203

To be 406 a prime number, it would have been required that 406 has only two divisors, i.e., itself and 1.

## Is 406 a deficient number?

Yes, 406 is a deficient number, that is to say 406 is a natural number that is strictly larger than the sum of its proper divisors, i.e., the divisors of 406 without 406 itself (that is 1 + 2 + 7 + 14 + 29 + 58 + 203 = 314).

## Parity of 406

406 is an even number, because it is evenly divisible by 2: 406 / 2 = 203.

## Is 406 a perfect square number?

A number is a perfect square (or a square number) if its square root is an integer; that is to say, it is the product of an integer with itself. Here, the square root of 406 is about 20.149.

Thus, the square root of 406 is not an integer, and therefore 406 is not a square number.

## What is the square number of 406?

The square of a number (here 406) is the result of the product of this number (406) by itself (i.e., 406 × 406); the square of 406 is sometimes called "raising 406 to the power 2", or "406 squared".

The square of 406 is 164 836 because 406 × 406 = 4062 = 164 836.

As a consequence, 406 is the square root of 164 836.

## Number of digits of 406

406 is a number with 3 digits.

## What are the multiples of 406?

The multiples of 406 are all integers evenly divisible by 406, that is all numbers such that the remainder of the division by 406 is zero. There are infinitely many multiples of 406. The smallest multiples of 406 are:

• 0: indeed, 0 is divisible by any natural number, and it is thus a multiple of 406 too, since 0 × 406 = 0
• 406: indeed, 406 is a multiple of itself, since 406 is evenly divisible by 406 (we have 406 / 406 = 1, so the remainder of this division is indeed zero)
• 812: indeed, 812 = 406 × 2
• 1 218: indeed, 1 218 = 406 × 3
• 1 624: indeed, 1 624 = 406 × 4
• 2 030: indeed, 2 030 = 406 × 5
• etc.

## How to determine whether an integer is a prime number?

To determine the primality of a number, several algorithms can be used. The most naive technique is to test all divisors strictly smaller to the number of which we want to determine the primality (here 406). First, we can eliminate all even numbers greater than 2 (and hence 4, 6, 8…). Then, we can stop this check when we reach the square root of the number of which we want to determine the primality (here the square root is about 20.149). Historically, the sieve of Eratosthenes (dating from the Greek mathematics) implements this technique in a relatively efficient manner.

More modern techniques include the sieve of Atkin, probabilistic algorithms, and the cyclotomic AKS test.

## Numbers near 406

• Preceding numbers: …404, 405
• Following numbers: 407, 408

## Nearest numbers from 406

• Preceding prime number: 401
• Following prime number: 409
Find out whether some integer is a prime number