It is possible to find out using mathematical methods whether a given integer is a prime number or not.
For 887, the answer is: yes, 887 is a prime number because it has only two distinct divisors: 1 and itself (887).
As a consequence, 887 is only a multiple of 1 and 887..
Since 887 is a prime number, 887 is also a deficient number, that is to say 887 is a natural integer that is strictly larger than the sum of its proper divisors, i.e., the divisors of 887 without 887 itself (that is 1, by definition!).
Parity of 887
887 is an odd number, because it is not evenly divisible by 2.
Is 887 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 887 is about 29.783.
Thus, the square root of 887 is not an integer, and therefore 887 is not a square number.
Anyway, 887 is a prime number, and a prime number cannot be a perfect square.
What is the square number of 887?
The square of a number (here 887) is the result of the product of this number (887) by itself (i.e., 887 × 887); the square of 887 is sometimes called "raising 887 to the power 2", or "887 squared".
As a consequence, 887 is the square root of 786 769.
Number of digits of 887
887 is a number with 3 digits.
What are the multiples of 887?
The multiples of 887 are all integers evenly divisible by 887, that is all numbers such that the remainder of the division by 887 is zero. There are infinitely many multiples of 887. The smallest multiples of 887 are:
- 0: indeed, 0 is divisible by any natural number, and it is thus a multiple of 887 too, since 0 × 887 = 0
- 887: indeed, 887 is a multiple of itself, since 887 is evenly divisible by 887 (we have 887 / 887 = 1, so the remainder of this division is indeed zero)
- 1 774: indeed, 1 774 = 887 × 2
- 2 661: indeed, 2 661 = 887 × 3
- 3 548: indeed, 3 548 = 887 × 4
- 4 435: indeed, 4 435 = 887 × 5
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 887). 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 29.783). 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.