What is the 7978th prime number?
The 7978th prime number is 81559. The next prime is 81563 (a gap of 4) and the one before is 81553.
Position
Pick any whole number from 1 to 10,000.
How to work it out
- 1
List the primes in order: 2, 3, 5, 7, 11, 13, ā¦ The 7978th one is 81559.
- 2
81559 is prime because no prime up to ā81559 ā 285.59 divides it.
- 3
The primes are spread thinner as numbers grow: by the prime number theorem the 7978th prime is close to 7978 Ć ln(7978) ā 71678, and here it is 81559.
- 4
81559 has no twin: neither 81557 nor 81561 is prime.
Primes around the 7978th
| Position | Prime | Gap from the previous |
|---|---|---|
| 7975 | 81547 | 14 |
| 7976 | 81551 | 4 |
| 7977 | 81553 | 2 |
| 7978 | 81559 | 6 |
| 7979 | 81563 | 4 |
| 7980 | 81569 | 6 |
| 7981 | 81611 | 42 |
Questions
What is the 7978th prime number?
81559.
Which prime number is 81559?
81559 is the 7978th prime number.
What is the sum of the first 7978 primes?
307,880,287.