Every Day Counts
Centred Triangular Prime Days
 
Age: 25,922 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
27 Jan 2025
25,931
9
70
04 Feb 2025
25,939
17
71
19 Nov 2025
26,227
305
71
10 May 2026
26,399
477
72
16 Feb 2027
26,681
759
73
15 Jul 2032
28,657
2,735
78
30 Jun 2036
30,103
4,181
82
04 Dec 2055
37,199
11,277
101
10 Nov 2061
39,367
13,445
107
12 Oct 2073
43,721
17,799
119
27 Nov 2075
44,497
18,575
121
11 Mar 2087
48,619
22,697
133
06 Jul 2133
65,537
39,615
179
19 Aug 2228
100,279
74,357
274
08 Mar 2252
108,881
82,959
298
09 Dec 2312
131,071
105,149
358
02 Apr 7771
2,124,679
2,098,757
5817
Ordinal
Day Age
Date
Age
1st
19
17 Feb 1954
0
2nd
31
01 Mar 1954
0
3rd
109
18 May 1954
0
4th
199
16 Aug 1954
0
5th
409
14 Mar 1955
1
6th
571
23 Aug 1955
1
7th
631
22 Oct 1955
1
8th
829
07 May 1956
2
9th
1,489
26 Feb 1958
4
10th
1,999
21 Jul 1959
5
11th
2,341
27 Jun 1960
6
12th
2,971
19 Mar 1962
8
13th
3,529
28 Sep 1963
9
14th
4,621
24 Sep 1966
12
15th
4,789
11 Mar 1967
13
16th
7,039
08 May 1973
19
17th
7,669
28 Jan 1975
20
18th
8,779
11 Feb 1978
24
19th
9,721
10 Sep 1980
26
20th
10,459
18 Sep 1982
28
21st
10,711
28 May 1983
29
22nd
13,681
15 Jul 1991
37
23rd
14,851
27 Sep 1994
40
24th
16,069
27 Jan 1998
43
25th
16,381
05 Dec 1998
44
26th
17,659
05 Jun 2002
48
27th
20,011
12 Nov 2008
54
28th
20,359
26 Oct 2009
55
29th
23,251
26 Sep 2017
63
30th
25,939
04 Feb 2025
71
1
31st
27,541
25 Jun 2029
75
32nd
29,191
31 Dec 2033
79
33rd
29,611
24 Feb 2035
81
34th
31,321
31 Oct 2039
85
35th
34,429
04 May 2048
94
36th
36,739
31 Aug 2054
100
37th
40,099
12 Nov 2063
109
38th
40,591
18 Mar 2065
111
39th
42,589
06 Sep 2070
116