Is 98 a prime number?
98 is not a prime number. Here is the quickest way to see it.
The answer
No. 98 is not a prime number: 2 × 49 = 98.
How to see that 98 is not prime
98 is even, and every even number can be divided by 2, so 2 is a factor as well as 1 and 98.
98 has 6 factors (1, 2, 7, 14, 49 and 98), which make 3 factor pairs.
Split 98 into prime factors
Split off the smallest prime each time, and keep going until every part is prime:
- 98 = 2 × 49
- 98 = 2 × 7 × 7
With the repeated primes written as powers, that is 2 × 7².
98 in the times tables
No fact from the 2 to 12 times tables, up to × 12, makes 98. Its smallest pair, 2 × 49, needs the 49 times table, which goes past 12.
Quick checks that catch 98
- The last digit, 8, is even, so 2 goes in.
98 at a glance
- In words
- ninety-eight
- In Roman numerals
- XCVIII
- Odd or even
- Even: it ends in 8
- Its factors add up to
- 171, or 73 without 98 itself, which makes 98 a deficient number
The numbers either side of 98
- 97 is prime: 2, 3, 5 and 7 do not go into it, and 11 × 11 is already past 97. Check 97 in full
- 99 is not prime. Its digits add up to 9 + 9 = 18, which is a multiple of 3. That means 99 is a multiple of 3 too, so 3 is a factor. Check 99 in full
Turn the digits round
98 backwards is 89. 89 is prime: 2, 3, 5 and 7 do not go into it, and 11 × 11 is already past 89. Check 89 in full
Related pages
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Questions parents ask
Which prime numbers are either side of 98?
97 below it and 101 above it, a gap of 4.
What is 98 squared?
98 × 98 = 9604.
What is the smallest number with as many factors as 98?
12. It has 6 factors, the same as 98.
Number facts are the base of 11+ maths
Factors, multiples, primes and square numbers come up all over 11+ maths, from simplifying fractions to ratio. The free diagnostic checks maths, English and both kinds of reasoning, and shows what to practise next. No card is required.