Is 100 a prime number?

Here is the answer to questions like: Is 100 a prime number? or is 100 a prime or a composite number?

Use the prime numbers calculator below to discover if any given number is a prime. You can also get a prime numbers chart with all primes before this given number.

Prime Numbers Calculator

Enter a integer number to analyse:

Ex.: 2, 3, 4, 11, 125, etc.

Number Analysis:

The prime factorization of 100 = 2²•5²

The number 100 is not a prime number because it is possible to factorize it. In other words, 100 can be divided by 1, by itself and at least by 2 and 5. This is a so called 'composite number'.

List of prime numbers before 100:

1	2	3	4	5	6	7	8	9	10	11	12	13	14
15	16	17	18	19	20	21	22	23	24	25	26	27	28
29	30	31	32	33	34	35	36	37	38	39	40	41	42
43	44	45	46	47	48	49	50	51	52	53	54	55	56
57	58	59	60	61	62	63	64	65	66	67	68	69	70
71	72	73	74	75	76	77	78	79	80	81	82	83	84
85	86	87	88	89	90	91	92	93	94	95	96	97	98
99	100

What is a prime number?

Definition of prime 1

An integer greater than one is called a prime number if its only positive divisors (factors) are one and itself. For example, the only divisors of 11 are 1 and 11, so 11 is a prime number, while the number 51 has divisors 3, 17 and 51 itself (51 = 3•17), making 51 not a prime number.

Definition of prime 2

A positive integer that is not divisible without remainder by any integer except itself and 1, with 1 often excluded.

Note that:

0 (zero) is not a prime number because it isn't divided by itself. Zero has an infinite number of divisors (any nonzero whole number divides zero). It cannot be written as a product of two factors, neither of which is itself, so zero is also not composite. More concisely, zero is not a prime or a composite number either.
1 (one) is neither a prime nor a composite number. One has only one positive divisor. It cannot be written as a product of two factors, neither of which is itself, so one is also not composite. THe number one falls in a class of numbers called units.

References: Why is the number one not prime? and 1 and 0: Prime or Composite?

Prime numbers calculator

Please link to this page! Just right click on the above image, choose copy link address, then past it in your HTML.