Is 878 a prime number?

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

For 878, the answer is: No, 878 is not a prime number.

The list of all positive divisors (i.e., the list of all integers that divide 878) is as follows: 1, 2, 439, 878.

For 878 to be a prime number, it would have been required that 878 has only two divisors, i.e., itself and 1.

Find out more:

What is a prime number?

As a consequence:

878 is a multiple of 1
878 is a multiple of 2
878 is a multiple of 439

For 878 to be a prime number, it would have been required that 878 has only two divisors, i.e., itself and 1.

However, 878 is a semiprime (also called biprime or 2-almost-prime), because it is the product of a two non-necessarily distinct prime numbers. Indeed, 878 = 2 x 439, where 2 and 439 are both prime numbers.

Is 878 a deficient number?

Yes, 878 is a deficient number, that is to say 878 is a natural number that is strictly larger than the sum of its proper divisors, i.e., the divisors of 878 without 878 itself (that is 1 + 2 + 439 = 442).

Parity of 878

878 is an even number, because it is evenly divisible by 2: 878 / 2 = 439.

Find out more:

What is an even number?

Is 878 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 878 is about 29.631.

Thus, the square root of 878 is not an integer, and therefore 878 is not a square number.

What is the square number of 878?

The square of a number (here 878) is the result of the product of this number (878) by itself (i.e., 878 × 878); the square of 878 is sometimes called "raising 878 to the power 2", or "878 squared".

The square of 878 is 770 884 because 878 × 878 = 878² = 770 884.

As a consequence, 878 is the square root of 770 884.

Number of digits of 878

878 is a number with 3 digits.

What are the multiples of 878?

The multiples of 878 are all integers evenly divisible by 878, that is all numbers such that the remainder of the division by 878 is zero. There are infinitely many multiples of 878. The smallest multiples of 878 are:

0: indeed, 0 is divisible by any natural number, and it is thus a multiple of 878 too, since 0 × 878 = 0
878: indeed, 878 is a multiple of itself, since 878 is evenly divisible by 878 (we have 878 / 878 = 1, so the remainder of this division is indeed zero)
1 756: indeed, 1 756 = 878 × 2
2 634: indeed, 2 634 = 878 × 3
3 512: indeed, 3 512 = 878 × 4
4 390: indeed, 4 390 = 878 × 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 878). 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 29.631). 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 878

Preceding numbers: …876, 877
Following numbers: 879, 880…

Nearest numbers from 878

Preceding prime number: 877
Following prime number: 881