Is 620 a prime number?

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

For 620, the answer is: No, 620 is not a prime number.

The list of all positive divisors (i.e., the list of all integers that divide 620) is as follows: 1, 2, 4, 5, 10, 20, 31, 62, 124, 155, 310, 620.

For 620 to be a prime number, it would have been required that 620 has only two divisors, i.e., itself and 1.

Find out more:

What is a prime number?

Actually, one can immediately see that 620 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 620 is 0, so it is divisible by 5 and is therefore not prime.

As a consequence:

620 is a multiple of 1
620 is a multiple of 2
620 is a multiple of 4
620 is a multiple of 5
620 is a multiple of 10
620 is a multiple of 20
620 is a multiple of 31
620 is a multiple of 62
620 is a multiple of 124
620 is a multiple of 155
620 is a multiple of 310

For 620 to be a prime number, it would have been required that 620 has only two divisors, i.e., itself and 1.

Is 620 a deficient number?

No, 620 is not a deficient number: to be deficient, 620 should have been such that 620 is larger than the sum of its proper divisors, i.e., the divisors of 620 without 620 itself (that is 1 + 2 + 4 + 5 + 10 + 20 + 31 + 62 + 124 + 155 + 310 = 724).

In fact, 620 is an abundant number; 620 is strictly smaller than the sum of its proper divisors (that is 1 + 2 + 4 + 5 + 10 + 20 + 31 + 62 + 124 + 155 + 310 = 724). The smallest abundant number is 12.

Parity of 620

620 is an even number, because it is evenly divisible by 2: 620 / 2 = 310.

Find out more:

What is an even number?

Is 620 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 620 is about 24.900.

Thus, the square root of 620 is not an integer, and therefore 620 is not a square number.

What is the square number of 620?

The square of a number (here 620) is the result of the product of this number (620) by itself (i.e., 620 × 620); the square of 620 is sometimes called "raising 620 to the power 2", or "620 squared".

The square of 620 is 384 400 because 620 × 620 = 620² = 384 400.

As a consequence, 620 is the square root of 384 400.

Number of digits of 620

620 is a number with 3 digits.

What are the multiples of 620?

The multiples of 620 are all integers evenly divisible by 620, that is all numbers such that the remainder of the division by 620 is zero. There are infinitely many multiples of 620. The smallest multiples of 620 are:

0: indeed, 0 is divisible by any natural number, and it is thus a multiple of 620 too, since 0 × 620 = 0
620: indeed, 620 is a multiple of itself, since 620 is evenly divisible by 620 (we have 620 / 620 = 1, so the remainder of this division is indeed zero)
1 240: indeed, 1 240 = 620 × 2
1 860: indeed, 1 860 = 620 × 3
2 480: indeed, 2 480 = 620 × 4
3 100: indeed, 3 100 = 620 × 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 620). 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 24.900). 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 620

Preceding numbers: …618, 619
Following numbers: 621, 622…

Nearest numbers from 620

Preceding prime number: 619
Following prime number: 631