Every Day Counts
Centred Triangular Prime Days
 
Age: 23,231 days
Date of birth
Your 29th Centred Triangular Prime Day is on
Thursday
when you will be
23,251 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
15 Oct 2026
23,251
20
63
15 Oct 2026
23,251
20
63
24 Dec 2026
23,321
90
63
18 Jun 2027
23,497
266
64
14 Oct 2028
23,981
750
65
03 Aug 2041
28,657
5,426
78
19 Jul 2045
30,103
6,872
82
22 Dec 2064
37,199
13,968
101
29 Nov 2070
39,367
16,136
107
31 Oct 2082
43,721
20,490
119
15 Dec 2084
44,497
21,266
121
29 Mar 2096
48,619
25,388
133
25 Jul 2142
65,537
42,306
179
07 Sep 2237
100,279
77,048
274
27 Mar 2261
108,881
85,650
298
28 Dec 2321
131,071
107,840
358
20 Apr 7780
2,124,679
2,101,448
5817
Ordinal
Day Age
Date
Age
1st
19
08 Mar 1963
0
2nd
31
20 Mar 1963
0
3rd
109
06 Jun 1963
0
4th
199
04 Sep 1963
0
5th
409
01 Apr 1964
1
6th
571
10 Sep 1964
1
7th
631
09 Nov 1964
1
8th
829
26 May 1965
2
9th
1,489
17 Mar 1967
4
10th
1,999
08 Aug 1968
5
11th
2,341
16 Jul 1969
6
12th
2,971
07 Apr 1971
8
13th
3,529
16 Oct 1972
9
14th
4,621
13 Oct 1975
12
15th
4,789
29 Mar 1976
13
16th
7,039
27 May 1982
19
17th
7,669
16 Feb 1984
20
18th
8,779
02 Mar 1987
24
19th
9,721
29 Sep 1989
26
20th
10,459
07 Oct 1991
28
21st
10,711
15 Jun 1992
29
22nd
13,681
02 Aug 2000
37
23rd
14,851
16 Oct 2003
40
24th
16,069
15 Feb 2007
43
25th
16,381
24 Dec 2007
44
26th
17,659
24 Jun 2011
48
27th
20,011
01 Dec 2017
54
28th
20,359
14 Nov 2018
55
29th
23,251
15 Oct 2026
63
1
30th
25,939
23 Feb 2034
71
31st
27,541
14 Jul 2038
75
32nd
29,191
19 Jan 2043
79
33rd
29,611
14 Mar 2044
81
34th
31,321
18 Nov 2048
85
35th
34,429
23 May 2057
94
36th
36,739
19 Sep 2063
100
37th
40,099
30 Nov 2072
109
38th
40,591
06 Apr 2074
111
39th
42,589
25 Sep 2079
116