Interprime Calculator

Interprime Calculator is a free online tool used to check if the number is an interprime.

Interprime Calculator

Eg, Is 234 an interprime number? Enter 234 into the input box and click Calculate button.

What is an interprime?

An interprime is the average of two consecutive odd primes. Note that it is an odd prime, so the prime 2 should be excluded. Consecutive primes indicate that there are no other primes between two primes. For example, 3 and 5 are consecutive primes. 7 and 11 are consecutive primes. 5 and 11 are not consecutive primes, because there is a prime number 7 between them.

Use tool to check if a number is prime: Prime and Composite Number Checker

Therefore, the first interprime is equal to the average of the first odd prime 3 and the second odd prime 5.

(3 + 5) / 2 = 4

4 is the first interprime.

How to check if a number is an interprime?

There are at least 4 steps to determine whether a number is an interprime:

1Find the prime number before the number.
2Find the prime number after the number.
3Calculate the average of the prime numbers found in the first and second steps.
4Compare the average and the number. If they are equal, the number is an interprime, otherwise, it is not.

For example, Is 2022 an interprime?

First, find the prime number before 2022, this prime number is 2017.

Second, find the prime number after 2022, this prime number is 2027.

Third, calculate the average of 2017 and 2027, which is (2017 + 2027) / 2 = 2022.

It can be seen from the above steps that 2022 is an interprime.

First 100 interprimes

4	6	9	12	15	18	21	26	30	34
39	42	45	50	56	60	64	69	72	76
81	86	93	99	102	105	108	111	120	129
134	138	144	150	154	160	165	170	176	180
186	192	195	198	205	217	225	228	231	236
240	246	254	260	266	270	274	279	282	288
300	309	312	315	324	334	342	348	351	356
363	370	376	381	386	393	399	405	414	420
426	432	436	441	446	453	459	462	465	473
483	489	495	501	506	515	522	532	544	552

How to use the interprime calculator

The procedure to use the interprime calculator is as follows:

1Enter the positive number.
2Click Calculate button to verify whether the input number is an interprime.
3Click the Reset button to start a new verification.

Solved examples using the interprime calculator

Example 1: Is 306 an interprime?

Enter 306 into the input box and click Calculate button, as shown in the figure, 306 is not an interprime.

The prime number before 306 is 293. The prime number after 306 is 307. Their average is 300.

Example 2: Is 4189 an interprime?

Enter 4189 into the input box and click Calculate button, as shown in the figure, 4189 is an interprime.

The prime number before 4189 is 4177. The prime number after 4189 is 4201. Their average is 4189.

Interprime Calculator