43138565 has 4 divisors (see below), whose sum is σ = 51766284. Its totient is φ = 34510848.

The previous prime is 43138549. The next prime is 43138619. The reversal of 43138565 is 56583134.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 23059204 + 20079361 = 4802^2 + 4481^2 .

It is a cyclic number.

It is not a de Polignac number, because 43138565 - 2⁴ = 43138549 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4313852 + ... + 4313861.

It is an arithmetic number, because the mean of its divisors is an integer number (12941571).

Almost surely, 2^43138565 is an apocalyptic number.

It is an amenable number.

43138565 is a deficient number, since it is larger than the sum of its proper divisors (8627719).

43138565 is an equidigital number, since it uses as much as digits as its factorization.

43138565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8627718.

The product of its digits is 43200, while the sum is 35.

The square root of 43138565 is about 6567.9955085247. The cubic root of 43138565 is about 350.7157190935.

The spelling of 43138565 in words is "forty-three million, one hundred thirty-eight thousand, five hundred sixty-five".