43009909 has 4 divisors (see below), whose sum is σ = 43046080. Its totient is φ = 42973740.

The previous prime is 43009907. The next prime is 43009937. The reversal of 43009909 is 90990034.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90990034 = 2 ⋅45495017.

It is a cyclic number.

It is not a de Polignac number, because 43009909 - 2¹ = 43009907 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43009907) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16239 + ... + 18700.

It is an arithmetic number, because the mean of its divisors is an integer number (10761520).

Almost surely, 2^43009909 is an apocalyptic number.

It is an amenable number.

43009909 is a deficient number, since it is larger than the sum of its proper divisors (36171).

43009909 is a wasteful number, since it uses less digits than its factorization.

43009909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36170.

The product of its (nonzero) digits is 8748, while the sum is 34.

The square root of 43009909 is about 6558.1940349459. The cubic root of 43009909 is about 350.3667149574.

The spelling of 43009909 in words is "forty-three million, nine thousand, nine hundred nine".