Is 679 a prime number?

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

For 679, the answer is: No, 679 is not a prime number.

The list of all positive divisors (i.e., the list of all integers that divide 679) is as follows: 1, 7, 97, 679.

For 679 to be a prime number, it would have been required that 679 has only two divisors, i.e., itself and 1.

Find out more:

What is a prime number?

As a consequence:

679 is a multiple of 1
679 is a multiple of 7
679 is a multiple of 97

For 679 to be a prime number, it would have been required that 679 has only two divisors, i.e., itself and 1.

However, 679 is a semiprime (also called biprime or 2-almost-prime), because it is the product of a two non-necessarily distinct prime numbers. Indeed, 679 = 7 x 97, where 7 and 97 are both prime numbers.

Is 679 a deficient number?

Yes, 679 is a deficient number, that is to say 679 is a natural number that is strictly larger than the sum of its proper divisors, i.e., the divisors of 679 without 679 itself (that is 1 + 7 + 97 = 105).

Parity of 679

679 is an odd number, because it is not evenly divisible by 2.

Find out more:

What is an even number?

Is 679 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 679 is about 26.058.

Thus, the square root of 679 is not an integer, and therefore 679 is not a square number.

What is the square number of 679?

The square of a number (here 679) is the result of the product of this number (679) by itself (i.e., 679 × 679); the square of 679 is sometimes called "raising 679 to the power 2", or "679 squared".

The square of 679 is 461 041 because 679 × 679 = 679² = 461 041.

As a consequence, 679 is the square root of 461 041.

Number of digits of 679

679 is a number with 3 digits.

What are the multiples of 679?

The multiples of 679 are all integers evenly divisible by 679, that is all numbers such that the remainder of the division by 679 is zero. There are infinitely many multiples of 679. The smallest multiples of 679 are:

0: indeed, 0 is divisible by any natural number, and it is thus a multiple of 679 too, since 0 × 679 = 0
679: indeed, 679 is a multiple of itself, since 679 is evenly divisible by 679 (we have 679 / 679 = 1, so the remainder of this division is indeed zero)
1 358: indeed, 1 358 = 679 × 2
2 037: indeed, 2 037 = 679 × 3
2 716: indeed, 2 716 = 679 × 4
3 395: indeed, 3 395 = 679 × 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 679). 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 26.058). 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 679

Preceding numbers: …677, 678
Following numbers: 680, 681…

Nearest numbers from 679

Preceding prime number: 677
Following prime number: 683