Hall of fame

Slow prime hall of fame

Large 64-bit primes exercised by this project (exact wheel trial division).
Times are indicative (depend on runner CPU and NUMBA_NUM_THREADS).

Prime	Formula / note	Typical optimized time (12 threads, order of magnitude)
1000000007	$10^9+7$	~0.03 ms
1000000009	$10^9+9$	~0.03 ms
2147483647	$2^{31}-1$ (M31)	~0.05 ms
999999999989	12-digit prime	~0.2–0.6 ms
2305843009213693951	$2^{61}-1$ (M61)	~0.3–0.5 s
9223372036854775783	near $2^{63}$	~0.7–0.8 s
18446744073709551557	largest prime $< 2^{64}$	~1 s class

Update this table when benchmark workflows or hardware change. Reproduce:

NUMBA_NUM_THREADS=$(nproc) python is_prime.py --lab 9223372036854775783
NUMBA_NUM_THREADS=$(nproc) python benchmarks/compare_speed.py --include-hard

Artifacts from CI Certificate of correctness and benchmark-json are authoritative for a given commit.