28

This number is a composite.

Single Curio View:   (Seek other curios for this number)
There are 28 (a perfect number) distinct pairs of primes that sum to a thousand: (3, 997), (17, 983), (23, 977), (29, 971), (47, 953), (53, 947), (59, 941), (71, 929), (89, 911), (113, 887), (137, 863), (173, 827), (179, 821), (191, 809), (227, 773), (239, 761), (257, 743), (281, 719), (317, 683), (347, 653), (353, 647), (359, 641), (383, 617), (401, 599), (431, 569), (443, 557), (479, 521), (491, 509). [Loungrides]

Submitted: 2012-06-26 15:22:05;   Last Modified: 2017-02-24 17:53:05.
Printed from the PrimePages <t5k.org> © G. L. Honaker and Chris K. Caldwell