10141...14571 (231-digits)

This number is a probable-prime (likely to be a prime but we have not (re-)proven it on this site).

                                                     1 0141514571 1014137215
3101412297 3610141087 3201014094 4905101408 0249110140 6600781014 0517666101
4037525510 1402328451 0140090436 1014023284 5101403752 5510140517 6661014066
0078101408 0249110140 9449051014 1087320101 4122973610 1413721531 0141514571

The smallest prime formed from the concatenation of n consecutive n-digit triangular numbers in the pattern {k, j, i, h, g, f, e, d, c, b, a, b, c, d, e, f, g, h, i, j, k}, i.e., {10141514571, 10141372153, 10141229736, 10141087320, 10140944905, 10140802491, 10140660078, 10140517666, 10140375255, 10140232845, 10140090436, 10140232845, 10140375255, 10140517666, 10140660078, 10140802491, 10140944905, 10141087320, 10141229736, 10141372153, 10141514571}, (case n=11). [Bajpai]