Every Day Counts
Centred Triangular Prime Days
 
Age: 23,245 days
Date of birth
Your 29th Centred Triangular Prime Day is on
Friday
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
10 Dec 2021
23,251
6
63
10 Dec 2021
23,251
6
63
18 Feb 2022
23,321
76
63
13 Aug 2022
23,497
252
64
10 Dec 2023
23,981
736
65
28 Sep 2036
28,657
5,412
78
13 Sep 2040
30,103
6,858
82
17 Feb 2060
37,199
13,954
101
24 Jan 2066
39,367
16,122
107
26 Dec 2077
43,721
20,476
119
10 Feb 2080
44,497
21,252
121
25 May 2091
48,619
25,374
133
19 Sep 2137
65,537
42,292
179
02 Nov 2232
100,279
77,034
274
22 May 2256
108,881
85,636
298
22 Feb 2317
131,071
107,826
358
16 Jun 7775
2,124,679
2,101,434
5817
Ordinal
Day Age
Date
Age
1st
19
03 May 1958
0
2nd
31
15 May 1958
0
3rd
109
01 Aug 1958
0
4th
199
30 Oct 1958
0
5th
409
28 May 1959
1
6th
571
06 Nov 1959
1
7th
631
05 Jan 1960
1
8th
829
21 Jul 1960
2
9th
1,489
12 May 1962
4
10th
1,999
04 Oct 1963
5
11th
2,341
10 Sep 1964
6
12th
2,971
02 Jun 1966
8
13th
3,529
12 Dec 1967
9
14th
4,621
08 Dec 1970
12
15th
4,789
25 May 1971
13
16th
7,039
22 Jul 1977
19
17th
7,669
13 Apr 1979
20
18th
8,779
27 Apr 1982
24
19th
9,721
24 Nov 1984
26
20th
10,459
02 Dec 1986
28
21st
10,711
11 Aug 1987
29
22nd
13,681
28 Sep 1995
37
23rd
14,851
11 Dec 1998
40
24th
16,069
12 Apr 2002
43
25th
16,381
18 Feb 2003
44
26th
17,659
19 Aug 2006
48
27th
20,011
26 Jan 2013
54
28th
20,359
09 Jan 2014
55
29th
23,251
10 Dec 2021
63
1
30th
25,939
20 Apr 2029
71
31st
27,541
08 Sep 2033
75
32nd
29,191
16 Mar 2038
79
33rd
29,611
10 May 2039
81
34th
31,321
14 Jan 2044
85
35th
34,429
18 Jul 2052
94
36th
36,739
14 Nov 2058
100
37th
40,099
26 Jan 2068
109
38th
40,591
01 Jun 2069
111
39th
42,589
20 Nov 2074
116