243043321 has 4 divisors (see below), whose sum is σ = 243081892. Its totient is φ = 243004752.

The previous prime is 243043313. The next prime is 243043327. The reversal of 243043321 is 123340342.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 123340342 = 2 ⋅61670171.

It can be written as a sum of positive squares in 2 ways, for example, as 162690025 + 80353296 = 12755^2 + 8964^2 .

It is a cyclic number.

It is not a de Polignac number, because 243043321 - 2³ = 243043313 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 243043292 and 243043301.

It is not an unprimeable number, because it can be changed into a prime (243043327) 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, 7386 + ... + 23251.

It is an arithmetic number, because the mean of its divisors is an integer number (60770473).

Almost surely, 2^243043321 is an apocalyptic number.

It is an amenable number.

243043321 is a deficient number, since it is larger than the sum of its proper divisors (38571).

243043321 is an equidigital number, since it uses as much as digits as its factorization.

243043321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38570.

The product of its (nonzero) digits is 1728, while the sum is 22.

The square root of 243043321 is about 15589.8467279188. The cubic root of 243043321 is about 624.0622275563.

Adding to 243043321 its reverse (123340342), we get a palindrome (366383663).

The spelling of 243043321 in words is "two hundred forty-three million, forty-three thousand, three hundred twenty-one".