Is 626 a prime number?

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

For 626, the answer is: No, 626 is not a prime number.

The list of all positive divisors (i.e., the list of all integers that divide 626) is as follows: 1, 2, 313, 626.

For 626 to be a prime number, it would have been required that 626 has only two divisors, i.e., itself and 1.

Find out more:

What is a prime number?

As a consequence:

626 is a multiple of 1
626 is a multiple of 2
626 is a multiple of 313

For 626 to be a prime number, it would have been required that 626 has only two divisors, i.e., itself and 1.

However, 626 is a semiprime (also called biprime or 2-almost-prime), because it is the product of a two non-necessarily distinct prime numbers. Indeed, 626 = 2 x 313, where 2 and 313 are both prime numbers.

Is 626 a deficient number?

Yes, 626 is a deficient number, that is to say 626 is a natural number that is strictly larger than the sum of its proper divisors, i.e., the divisors of 626 without 626 itself (that is 1 + 2 + 313 = 316).

Parity of 626

626 is an even number, because it is evenly divisible by 2: 626 / 2 = 313.

Find out more:

What is an even number?

Is 626 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 626 is about 25.020.

Thus, the square root of 626 is not an integer, and therefore 626 is not a square number.

What is the square number of 626?

The square of a number (here 626) is the result of the product of this number (626) by itself (i.e., 626 × 626); the square of 626 is sometimes called "raising 626 to the power 2", or "626 squared".

The square of 626 is 391 876 because 626 × 626 = 626² = 391 876.

As a consequence, 626 is the square root of 391 876.

Number of digits of 626

626 is a number with 3 digits.

What are the multiples of 626?

The multiples of 626 are all integers evenly divisible by 626, that is all numbers such that the remainder of the division by 626 is zero. There are infinitely many multiples of 626. The smallest multiples of 626 are:

0: indeed, 0 is divisible by any natural number, and it is thus a multiple of 626 too, since 0 × 626 = 0
626: indeed, 626 is a multiple of itself, since 626 is evenly divisible by 626 (we have 626 / 626 = 1, so the remainder of this division is indeed zero)
1 252: indeed, 1 252 = 626 × 2
1 878: indeed, 1 878 = 626 × 3
2 504: indeed, 2 504 = 626 × 4
3 130: indeed, 3 130 = 626 × 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 626). 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 25.020). 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 626

Preceding numbers: …624, 625
Following numbers: 627, 628…

Nearest numbers from 626

Preceding prime number: 619
Following prime number: 631