Is 890 a prime number?

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

For 890, the answer is: No, 890 is not a prime number.

The list of all positive divisors (i.e., the list of all integers that divide 890) is as follows: 1, 2, 5, 10, 89, 178, 445, 890.

For 890 to be a prime number, it would have been required that 890 has only two divisors, i.e., itself and 1.

Find out more:

What is a prime number?

Actually, one can immediately see that 890 cannot be prime, because 5 is one of its divisors: indeed, a number ending with 0 or 5 has necessarily 5 among its divisors. The last digit of 890 is 0, so it is divisible by 5 and is therefore not prime.

As a consequence:

890 is a multiple of 1
890 is a multiple of 2
890 is a multiple of 5
890 is a multiple of 10
890 is a multiple of 89
890 is a multiple of 178
890 is a multiple of 445

For 890 to be a prime number, it would have been required that 890 has only two divisors, i.e., itself and 1.

Is 890 a deficient number?

Yes, 890 is a deficient number, that is to say 890 is a natural number that is strictly larger than the sum of its proper divisors, i.e., the divisors of 890 without 890 itself (that is 1 + 2 + 5 + 10 + 89 + 178 + 445 = 730).

Parity of 890

890 is an even number, because it is evenly divisible by 2: 890 / 2 = 445.

Find out more:

What is an even number?

Is 890 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 890 is about 29.833.

Thus, the square root of 890 is not an integer, and therefore 890 is not a square number.

What is the square number of 890?

The square of a number (here 890) is the result of the product of this number (890) by itself (i.e., 890 × 890); the square of 890 is sometimes called "raising 890 to the power 2", or "890 squared".

The square of 890 is 792 100 because 890 × 890 = 890² = 792 100.

As a consequence, 890 is the square root of 792 100.

Number of digits of 890

890 is a number with 3 digits.

What are the multiples of 890?

The multiples of 890 are all integers evenly divisible by 890, that is all numbers such that the remainder of the division by 890 is zero. There are infinitely many multiples of 890. The smallest multiples of 890 are:

0: indeed, 0 is divisible by any natural number, and it is thus a multiple of 890 too, since 0 × 890 = 0
890: indeed, 890 is a multiple of itself, since 890 is evenly divisible by 890 (we have 890 / 890 = 1, so the remainder of this division is indeed zero)
1 780: indeed, 1 780 = 890 × 2
2 670: indeed, 2 670 = 890 × 3
3 560: indeed, 3 560 = 890 × 4
4 450: indeed, 4 450 = 890 × 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 890). 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 29.833). 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 890

Preceding numbers: …888, 889
Following numbers: 891, 892…

Nearest numbers from 890

Preceding prime number: 887
Following prime number: 907