Mathematically 47

Forty Seven (47)

1. It is a prime number.

2. It is a Lucas number. The Lucas series goes like – 1, 3, 4, 7, 11, 18, 29, 47—

3. It is the first of three consecutive primes (47, 53, 59) that are spaced an equal distance apart. The first such set is (3, 5, 7) and next set is (151, 157, 163)

4. It is the largest number of cubes that cannot tile a cube.

5. The combination of 2 makes an interesting pattern.
47 + 2 = 49 and 49 x 2 = 94
497 + 2 = 499 and 497 x 2 = 994
4997 + 2 = 4999 and 4997 x 2 =9994
49997 + 2 = 49999 and 49997 x 2 = 99994
--------so on
the above pattern shows the same digits in reverse order in two operations.

6. It is the difference of squares of two consecutive numbers.
47 = 24^2 – 23^2

7. There are 47 occurrences of 47 in the first thousand prime numbers.

8. The atomic number of Silver is 47.

9. It is a carol number. A carol number is an integer of the form of 4n – 2n+1 – 1. The first few number are – 1, 7, 47, 223--- This was discovered by Cletus Emmanuel who named it after his friend Carol G Kimon.


Dr Rajesh Kumar Thakur