43406509 has 2 divisors, whose sum is σ = 43406510. Its totient is φ = 43406508.

The previous prime is 43406483. The next prime is 43406537. The reversal of 43406509 is 90560434.

43406509 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 32661225 + 10745284 = 5715^2 + 3278^2 .

It is a cyclic number.

It is not a de Polignac number, because 43406509 - 2¹¹ = 43404461 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43406549) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21703254 + 21703255.

It is an arithmetic number, because the mean of its divisors is an integer number (21703255).

Almost surely, 2^43406509 is an apocalyptic number.

It is an amenable number.

43406509 is a deficient number, since it is larger than the sum of its proper divisors (1).

43406509 is an equidigital number, since it uses as much as digits as its factorization.

43406509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12960, while the sum is 31.

The square root of 43406509 is about 6588.3616324546. The cubic root of 43406509 is about 351.4403474315.

The spelling of 43406509 in words is "forty-three million, four hundred six thousand, five hundred nine".