243423409 has 2 divisors, whose sum is σ = 243423410. Its totient is φ = 243423408.

The previous prime is 243423347. The next prime is 243423413. The reversal of 243423409 is 904324342.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 234181809 + 9241600 = 15303^2 + 3040^2 .

It is a cyclic number.

It is not a de Polignac number, because 243423409 - 2¹¹ = 243421361 is a prime.

It is equal to p_13338814 and since 243423409 and 13338814 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (243423449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121711704 + 121711705.

It is an arithmetic number, because the mean of its divisors is an integer number (121711705).

Almost surely, 2^243423409 is an apocalyptic number.

It is an amenable number.

243423409 is a deficient number, since it is larger than the sum of its proper divisors (1).

243423409 is an equidigital number, since it uses as much as digits as its factorization.

243423409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 31.

The square root of 243423409 is about 15602.0322073761. The cubic root of 243423409 is about 624.3873753819.

The spelling of 243423409 in words is "two hundred forty-three million, four hundred twenty-three thousand, four hundred nine".