Is 390 a prime number? What are the divisors of 390?

Parity of 390

390 is an even number, because it is evenly divisible by 2: 390 / 2 = 195.

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Is 390 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 390 is about 19.748.

Thus, the square root of 390 is not an integer, and therefore 390 is not a square number.

What is the square number of 390?

The square of a number (here 390) is the result of the product of this number (390) by itself (i.e., 390 × 390); the square of 390 is sometimes called "raising 390 to the power 2", or "390 squared".

The square of 390 is 152 100 because 390 × 390 = 3902 = 152 100.

As a consequence, 390 is the square root of 152 100.

Number of digits of 390

390 is a number with 3 digits.

What are the multiples of 390?

The multiples of 390 are all integers evenly divisible by 390, that is all numbers such that the remainder of the division by 390 is zero. There are infinitely many multiples of 390. The smallest multiples of 390 are:

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 390). 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 19.748). 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 390

  • Preceding numbers: …388, 389
  • Following numbers: 391, 392

Nearest numbers from 390

  • Preceding prime number: 389
  • Following prime number: 397
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