Primes

This is a diversion, but I created a simple program using BigInteger in Java to create prime numbers.

These are some prime numbers I calculated.  They have NOT been verified.  It is much,much more difficult to verify than to prove one.  My goal is to find a really big one, 20,000 digits or more and post it publicly. Time is in milliseconds.

Possible primes:
210*(10^397+16)-17, number of digits: 400, time:  2572.  Verified by WolframAlpha.
210*(10^447+15)-19, number of digits: 450, time: 3831
210*(10^497+18)-19, number of digits: 500, time: 5893
210*(10^547+37)+13, number of digits: 550, time: 15780
210*(10^597+17)-17, number of digits: 600, time: 8751
210*(10^647+4)-17, number of digits: 650, time: 2844
210*(10^697+8)-19, number of digits: 700, time: 6498
210*(10^797+89)+13,number of digits: 800, time: 89458
210*(10^897+6)-17,number of digits: 900, time: 9726
210*(10^997+72)-13,number of digits: 1000, time: 165535. This is a titanic prime! Verified by WolframAlpha.

210*(10^1097+146)+13, number of digits: 1100, time: 459584


210*(10^1197+162)+11, number of digits: 1200, time: 670547   This is a number starting with 21, about 1200 zeroes and ending in 34031.


210*(10^1247+96)+17, number of digits: 1250, time:  446148. This number ends in 20177.


210*(10^1297+22)-17,number of digits: 1300, time: 120943. It ends in 4603.


210*(10^1397+179)+17, number of digits: 1400, time:  1116773. It ends in 37607.


And that's about all I have time for.  Interesting. The first titanic prime (Mersenne prime 19) wasn't discovered until 1961.