Every Day Counts
Centred Triangular Prime Days
 
Age: 25,923 days
Date of birth
Your 30th Centred Triangular Prime Day is on
Tuesday
when you will be
25,939 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
26 Oct 2026
25,931
8
70
03 Nov 2026
25,939
16
71
18 Aug 2027
26,227
304
71
06 Feb 2028
26,399
476
72
14 Nov 2028
26,681
758
73
13 Apr 2034
28,657
2,734
78
29 Mar 2038
30,103
4,180
82
01 Sep 2057
37,199
11,276
101
09 Aug 2063
39,367
13,444
107
11 Jul 2075
43,721
17,798
119
25 Aug 2077
44,497
18,574
121
07 Dec 2088
48,619
22,696
133
04 Apr 2135
65,537
39,614
179
18 May 2230
100,279
74,356
274
05 Dec 2253
108,881
82,958
298
07 Sep 2314
131,071
105,148
358
29 Dec 7772
2,124,679
2,098,756
5817
Ordinal
Day Age
Date
Age
1st
19
16 Nov 1955
0
2nd
31
28 Nov 1955
0
3rd
109
14 Feb 1956
0
4th
199
14 May 1956
0
5th
409
10 Dec 1956
1
6th
571
21 May 1957
1
7th
631
20 Jul 1957
1
8th
829
03 Feb 1958
2
9th
1,489
25 Nov 1959
4
10th
1,999
18 Apr 1961
5
11th
2,341
26 Mar 1962
6
12th
2,971
16 Dec 1963
8
13th
3,529
26 Jun 1965
9
14th
4,621
22 Jun 1968
12
15th
4,789
07 Dec 1968
13
16th
7,039
04 Feb 1975
19
17th
7,669
26 Oct 1976
20
18th
8,779
10 Nov 1979
24
19th
9,721
09 Jun 1982
26
20th
10,459
16 Jun 1984
28
21st
10,711
23 Feb 1985
29
22nd
13,681
12 Apr 1993
37
23rd
14,851
25 Jun 1996
40
24th
16,069
26 Oct 1999
43
25th
16,381
02 Sep 2000
44
26th
17,659
03 Mar 2004
48
27th
20,011
11 Aug 2010
54
28th
20,359
25 Jul 2011
55
29th
23,251
25 Jun 2019
63
30th
25,939
03 Nov 2026
71
1
31st
27,541
24 Mar 2031
75
32nd
29,191
29 Sep 2035
79
33rd
29,611
22 Nov 2036
81
34th
31,321
29 Jul 2041
85
35th
34,429
31 Jan 2050
94
36th
36,739
29 May 2056
100
37th
40,099
10 Aug 2065
109
38th
40,591
15 Dec 2066
111
39th
42,589
04 Jun 2072
116