• 43 can be written using four 4's:

• Deleting all the even digits from 2^{43} = 8796093022208 we obtain a prime (7993).

43 has 2 divisors, whose sum is σ = 44. Its totient is φ = 42.

The previous prime is 41. The next prime is 47. The reversal of 43 is 34.

43 is nontrivially palindromic in base 6.

43 is an esthetic number in base 10 and base 13, because in such bases its adjacent digits differ by 1.

It is a weak prime.

43 is a truncatable prime.

It is a cyclic number.

It is not a de Polignac number, because 43 - 2^{1} = 41 is a prime.

Together with 41, it forms a pair of twin primes.

It is the 7-th Jacobsthal number.

It is a magnanimous number.

It is a d-powerful number, because it can be written as **3**^{3} + **4**^{2} .

It is an alternating number because its digits alternate between even and odd.

It is the 7-th Hogben number.

43 is a lucky number.

43 is a nontrivial repdigit in base 6.

It is a plaindrome in base 4, base 5, base 6, base 9, base 11, base 12, base 13, base 15 and base 16.

It is a nialpdrome in base 6, base 7, base 8, base 10 and base 14.

It is a zygodrome in base 6.

It is a panconsummate number.

It is a nontrivial repunit in base 6.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21 + 22.

It is an arithmetic number, because the mean of its divisors is an integer number (22).

43 is the 4-th centered heptagonal number.

43 is a deficient number, since it is larger than the sum of its proper divisors (1).

43 is an equidigital number, since it uses as much as digits as its factorization.

It is an anagram of its base 13 representation: 43 = (34)_{13}.

43 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12, while the sum is 7.

The square root of 43 is about 6.5574385243. The cubic root of 43 is about 3.5033980604.

Adding to 43 its product of digits (12), we get a palindrome (55).

Adding to 43 its reverse (34), we get a palindrome (77).

The spelling of 43 in words is "forty-three", and thus it is an aban number, an iban number, and an uban number.

• e-mail: info -at- numbersaplenty.com • Privacy notice • done in 0.104 sec. • engine limits •