Is 822 a prime number?

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

For 822, the answer is: No, 822 is not a prime number.

The list of all positive divisors (i.e., the list of all integers that divide 822) is as follows: 1, 2, 3, 6, 137, 274, 411, 822.

For 822 to be a prime number, it would have been required that 822 has only two divisors, i.e., itself and 1.

Find out more:

What is a prime number?

As a consequence:

822 is a multiple of 1
822 is a multiple of 2
822 is a multiple of 3
822 is a multiple of 6
822 is a multiple of 137
822 is a multiple of 274
822 is a multiple of 411

For 822 to be a prime number, it would have been required that 822 has only two divisors, i.e., itself and 1.

Is 822 a deficient number?

No, 822 is not a deficient number: to be deficient, 822 should have been such that 822 is larger than the sum of its proper divisors, i.e., the divisors of 822 without 822 itself (that is 1 + 2 + 3 + 6 + 137 + 274 + 411 = 834).

In fact, 822 is an abundant number; 822 is strictly smaller than the sum of its proper divisors (that is 1 + 2 + 3 + 6 + 137 + 274 + 411 = 834). The smallest abundant number is 12.

Parity of 822

822 is an even number, because it is evenly divisible by 2: 822 / 2 = 411.

Find out more:

What is an even number?

Is 822 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 822 is about 28.671.

Thus, the square root of 822 is not an integer, and therefore 822 is not a square number.

What is the square number of 822?

The square of a number (here 822) is the result of the product of this number (822) by itself (i.e., 822 × 822); the square of 822 is sometimes called "raising 822 to the power 2", or "822 squared".

The square of 822 is 675 684 because 822 × 822 = 822² = 675 684.

As a consequence, 822 is the square root of 675 684.

Number of digits of 822

822 is a number with 3 digits.

What are the multiples of 822?

The multiples of 822 are all integers evenly divisible by 822, that is all numbers such that the remainder of the division by 822 is zero. There are infinitely many multiples of 822. The smallest multiples of 822 are:

0: indeed, 0 is divisible by any natural number, and it is thus a multiple of 822 too, since 0 × 822 = 0
822: indeed, 822 is a multiple of itself, since 822 is evenly divisible by 822 (we have 822 / 822 = 1, so the remainder of this division is indeed zero)
1 644: indeed, 1 644 = 822 × 2
2 466: indeed, 2 466 = 822 × 3
3 288: indeed, 3 288 = 822 × 4
4 110: indeed, 4 110 = 822 × 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 822). 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 28.671). 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 822

Preceding numbers: …820, 821
Following numbers: 823, 824…

Nearest numbers from 822

Preceding prime number: 821
Following prime number: 823