Every Day Counts
Centred Triangular Prime Days
 
Age: 31,304 days
Date of birth
Your 34th Centred Triangular Prime Day is on
Tuesday
when you will be
31,321 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
29 Apr 2025
31,307
3
85
13 May 2025
31,321
17
85
21 Nov 2025
31,513
209
86
17 Feb 2026
31,601
297
86
12 Jan 2031
33,391
2,087
91
23 Mar 2031
33,461
2,157
91
16 Jun 2041
37,199
5,895
101
24 May 2047
39,367
8,063
107
25 Apr 2059
43,721
12,417
119
09 Jun 2061
44,497
13,193
121
21 Sep 2072
48,619
17,315
133
17 Jan 2119
65,537
34,233
179
02 Mar 2214
100,279
68,975
274
19 Sep 2237
108,881
77,577
298
21 Jun 2298
131,071
99,767
358
13 Oct 7756
2,124,679
2,093,375
5817
Ordinal
Day Age
Date
Age
1st
19
31 Aug 1939
0
2nd
31
12 Sep 1939
0
3rd
109
29 Nov 1939
0
4th
199
27 Feb 1940
0
5th
409
24 Sep 1940
1
6th
571
05 Mar 1941
1
7th
631
04 May 1941
1
8th
829
18 Nov 1941
2
9th
1,489
09 Sep 1943
4
10th
1,999
31 Jan 1945
5
11th
2,341
08 Jan 1946
6
12th
2,971
30 Sep 1947
8
13th
3,529
10 Apr 1949
9
14th
4,621
06 Apr 1952
12
15th
4,789
21 Sep 1952
13
16th
7,039
19 Nov 1958
19
17th
7,669
10 Aug 1960
20
18th
8,779
25 Aug 1963
24
19th
9,721
24 Mar 1966
26
20th
10,459
31 Mar 1968
28
21st
10,711
08 Dec 1968
29
22nd
13,681
25 Jan 1977
37
23rd
14,851
09 Apr 1980
40
24th
16,069
10 Aug 1983
43
25th
16,381
17 Jun 1984
44
26th
17,659
17 Dec 1987
48
27th
20,011
26 May 1994
54
28th
20,359
09 May 1995
55
29th
23,251
09 Apr 2003
63
30th
25,939
18 Aug 2010
71
31st
27,541
06 Jan 2015
75
32nd
29,191
14 Jul 2019
79
33rd
29,611
06 Sep 2020
81
34th
31,321
13 May 2025
85
1
35th
34,429
15 Nov 2033
94
36th
36,739
13 Mar 2040
100
37th
40,099
25 May 2049
109
38th
40,591
29 Sep 2050
111
39th
42,589
19 Mar 2056
116