243400247 has 2 divisors, whose sum is σ = 243400248. Its totient is φ = 243400246.

The previous prime is 243400181. The next prime is 243400301. The reversal of 243400247 is 742004342.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 243400247 - 2¹⁰ = 243399223 is a prime.

It is a super-2 number, since 2×243400247² = 118487360479322018, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243400147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121700123 + 121700124.

It is an arithmetic number, because the mean of its divisors is an integer number (121700124).

Almost surely, 2^243400247 is an apocalyptic number.

243400247 is a deficient number, since it is larger than the sum of its proper divisors (1).

243400247 is an equidigital number, since it uses as much as digits as its factorization.

243400247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5376, while the sum is 26.

The square root of 243400247 is about 15601.2899146192. The cubic root of 243400247 is about 624.3675710430.

Adding to 243400247 its reverse (742004342), we get a palindrome (985404589).

The spelling of 243400247 in words is "two hundred forty-three million, four hundred thousand, two hundred forty-seven".