Every Day Counts
Centred Triangular Prime Days
 
Age: 23,235 days
Date of birth
Your 29th Centred Triangular Prime Day is on
Sunday
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
13 Sep 2026
23,251
16
63
13 Sep 2026
23,251
16
63
22 Nov 2026
23,321
86
63
17 May 2027
23,497
262
64
12 Sep 2028
23,981
746
65
02 Jul 2041
28,657
5,422
78
17 Jun 2045
30,103
6,868
82
20 Nov 2064
37,199
13,964
101
28 Oct 2070
39,367
16,132
107
29 Sep 2082
43,721
20,486
119
13 Nov 2084
44,497
21,262
121
26 Feb 2096
48,619
25,384
133
23 Jun 2142
65,537
42,302
179
06 Aug 2237
100,279
77,044
274
23 Feb 2261
108,881
85,646
298
26 Nov 2321
131,071
107,836
358
19 Mar 7780
2,124,679
2,101,444
5817
Ordinal
Day Age
Date
Age
1st
19
04 Feb 1963
0
2nd
31
16 Feb 1963
0
3rd
109
05 May 1963
0
4th
199
03 Aug 1963
0
5th
409
29 Feb 1964
1
6th
571
09 Aug 1964
1
7th
631
08 Oct 1964
1
8th
829
24 Apr 1965
2
9th
1,489
13 Feb 1967
4
10th
1,999
07 Jul 1968
5
11th
2,341
14 Jun 1969
6
12th
2,971
06 Mar 1971
8
13th
3,529
14 Sep 1972
9
14th
4,621
11 Sep 1975
12
15th
4,789
26 Feb 1976
13
16th
7,039
25 Apr 1982
19
17th
7,669
15 Jan 1984
20
18th
8,779
29 Jan 1987
24
19th
9,721
28 Aug 1989
26
20th
10,459
05 Sep 1991
28
21st
10,711
14 May 1992
29
22nd
13,681
01 Jul 2000
37
23rd
14,851
14 Sep 2003
40
24th
16,069
14 Jan 2007
43
25th
16,381
22 Nov 2007
44
26th
17,659
23 May 2011
48
27th
20,011
30 Oct 2017
54
28th
20,359
13 Oct 2018
55
29th
23,251
13 Sep 2026
63
1
30th
25,939
22 Jan 2034
71
31st
27,541
12 Jun 2038
75
32nd
29,191
18 Dec 2042
79
33rd
29,611
11 Feb 2044
81
34th
31,321
17 Oct 2048
85
35th
34,429
21 Apr 2057
94
36th
36,739
18 Aug 2063
100
37th
40,099
29 Oct 2072
109
38th
40,591
05 Mar 2074
111
39th
42,589
24 Aug 2079
116