Every Day Counts
Centred Triangular Prime Days
 
Age: 14,846 days
Date of birth
Your 23rd Centred Triangular Prime Day is on
Friday
when you will be
14,851 days old

A centred triangular prime is a centred triangular number that is prime.

Centred triangular numbers are of the form (3n2 + 3n + 2) / 2

A centred triangular number is a centred figurate number that represents a triangle with a dot in the centre and all other dots surrounding the centre in successive triangular layers.

The figures for the first four centred triangular numbers are shown below:

Remind me, please


Next Prime Events
Day Age
Event
Days Ahead
Year Age
05 Sep 2025
14,851
5
40
05 Sep 2025
14,851
5
40
11 Dec 2026
15,313
467
41
09 Mar 2027
15,401
555
42
28 Apr 2027
15,451
605
42
04 Mar 2029
16,127
1,281
44
10 Aug 2030
16,651
1,805
45
18 Feb 2031
16,843
1,997
46
03 Dec 2032
17,497
2,651
47
18 Oct 2034
18,181
3,335
49
09 Feb 2038
19,391
4,545
53
09 Aug 2039
19,937
5,091
54
24 Jun 2063
28,657
13,811
78
21 Sep 2104
43,721
28,875
119
18 Feb 2118
48,619
33,773
133
14 Jun 2164
65,537
50,691
179
29 Jul 2259
100,279
85,433
274
18 Nov 2343
131,071
116,225
358
Ordinal
Day Age
Date
Age
1st
19
26 Jan 1985
0
2nd
31
07 Feb 1985
0
3rd
109
26 Apr 1985
0
4th
199
25 Jul 1985
0
5th
409
20 Feb 1986
1
6th
571
01 Aug 1986
1
7th
631
30 Sep 1986
1
8th
829
16 Apr 1987
2
9th
1,489
04 Feb 1989
4
10th
1,999
29 Jun 1990
5
11th
2,341
06 Jun 1991
6
12th
2,971
25 Feb 1993
8
13th
3,529
06 Sep 1994
9
14th
4,621
02 Sep 1997
12
15th
4,789
17 Feb 1998
13
16th
7,039
16 Apr 2004
19
17th
7,669
06 Jan 2006
20
18th
8,779
20 Jan 2009
24
19th
9,721
20 Aug 2011
26
20th
10,459
27 Aug 2013
28
21st
10,711
06 May 2014
29
22nd
13,681
23 Jun 2022
37
23rd
14,851
05 Sep 2025
40
1
24th
16,069
05 Jan 2029
43
25th
16,381
13 Nov 2029
44
26th
17,659
14 May 2033
48
27th
20,011
22 Oct 2039
54
28th
20,359
04 Oct 2040
55
29th
23,251
04 Sep 2048
63
30th
25,939
14 Jan 2056
71
31st
27,541
03 Jun 2060
75
32nd
29,191
09 Dec 2064
79
33rd
29,611
02 Feb 2066
81
34th
31,321
09 Oct 2070
85
35th
34,429
13 Apr 2079
94
36th
36,739
09 Aug 2085
100
37th
40,099
21 Oct 2094
109
38th
40,591
25 Feb 2096
111
39th
42,589
16 Aug 2101
116