243331009 has 4 divisors (see below), whose sum is σ = 244066480. Its totient is φ = 242595540.

The previous prime is 243330991. The next prime is 243331087. The reversal of 243331009 is 900133342.

It is a happy number.

243331009 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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.

It is a cyclic number.

It is not a de Polignac number, because 243331009 - 2⁵ = 243330977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (243331409) 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, 367239 + ... + 367900.

It is an arithmetic number, because the mean of its divisors is an integer number (61016620).

Almost surely, 2^243331009 is an apocalyptic number.

It is an amenable number.

243331009 is a deficient number, since it is larger than the sum of its proper divisors (735471).

243331009 is an equidigital number, since it uses as much as digits as its factorization.

243331009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 735470.

The product of its (nonzero) digits is 1944, while the sum is 25.

The square root of 243331009 is about 15599.0707736070. The cubic root of 243331009 is about 624.3083625826.

The spelling of 243331009 in words is "two hundred forty-three million, three hundred thirty-one thousand, nine".