243400457 has 2 divisors, whose sum is σ = 243400458. Its totient is φ = 243400456.

The previous prime is 243400427. The next prime is 243400459. The reversal of 243400457 is 754004342.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 184172041 + 59228416 = 13571^2 + 7696^2 .

It is a cyclic number.

It is not a de Polignac number, because 243400457 - 2¹⁴ = 243384073 is a prime.

Together with 243400459, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (243400459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121700228 + 121700229.

It is an arithmetic number, because the mean of its divisors is an integer number (121700229).

Almost surely, 2^243400457 is an apocalyptic number.

It is an amenable number.

243400457 is a deficient number, since it is larger than the sum of its proper divisors (1).

243400457 is an equidigital number, since it uses as much as digits as its factorization.

243400457 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13440, while the sum is 29.

The square root of 243400457 is about 15601.2966448305. The cubic root of 243400457 is about 624.3677506061.

Adding to 243400457 its reverse (754004342), we get a palindrome (997404799).

The spelling of 243400457 in words is "two hundred forty-three million, four hundred thousand, four hundred fifty-seven".