Prime numbers between 80001 and 81,000
There are 88 prime numbers between 80001 and 81,000: 80021, 80039, 80051, 80071, 80077, 80107, 80111, 80141, 80147, 80149, 80153, 80167, 80173, 80177, 80191, 80207, 80209, 80221, 80231, 80233, 80239, 80251, 80263, 80273, 80279, 80287, 80309, 80317, 80329, 80341, 80347, 80363, 80369, 80387, 80407, 80429, 80447, 80449, 80471, 80473, 80489, 80491, 80513, 80527, 80537, 80557, 80567, 80599, 80603, 80611, 80621, 80627, 80629, 80651, 80657, 80669, 80671, 80677, 80681, 80683, 80687, 80701, 80713, 80737, 80747, 80749, 80761, 80777, 80779, 80783, 80789, 80803, 80809, 80819, 80831, 80833, 80849, 80863, 80897, 80909, 80911, 80917, 80923, 80929, 80933, 80953, 80963, 80989.
How to work it out
- 1
A prime has exactly two factors, 1 and itself. To list them, cross out multiples of 2, then 3, then 5, and so on up to ā81000 ā 284.6 (the sieve of Eratosthenes). What is left are the primes.
- 2
That leaves 88 primes between 80001 and 81,000, with a total of 7,085,320.
- 3
The biggest gap between neighbouring primes in this range is 34, after 80863 (the next prime is 80897). There are 13 twin prime pairs (primes 2 apart), the first ones (80147, 80149), (80207, 80209), (80231, 80233), (80447, 80449), (80471, 80473), (80489, 80491), (80627, 80629), (80669, 80671).
How many primes in each part
| Range | Primes | Share of the numbers |
|---|---|---|
| 80,001 to 81,000 | 88 | 8.8% |
Questions
How many prime numbers are there between 80001 and 81,000?
88.
What is the biggest prime number below 81,000?
80989.
What is the first prime number after 80000?
80021.