243121447 has 2 divisors, whose sum is σ = 243121448. Its totient is φ = 243121446.

The previous prime is 243121429. The next prime is 243121453. The reversal of 243121447 is 744121342.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243121447 is a prime.

It is a Chen prime.

It is equal to p_13323196 and since 243121447 and 13323196 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243121457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121560723 + 121560724.

It is an arithmetic number, because the mean of its divisors is an integer number (121560724).

Almost surely, 2^243121447 is an apocalyptic number.

243121447 is a deficient number, since it is larger than the sum of its proper divisors (1).

243121447 is an equidigital number, since it uses as much as digits as its factorization.

243121447 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5376, while the sum is 28.

The square root of 243121447 is about 15592.3521958683. The cubic root of 243121447 is about 624.1290884245.

Adding to 243121447 its reverse (744121342), we get a palindrome (987242789).

The spelling of 243121447 in words is "two hundred forty-three million, one hundred twenty-one thousand, four hundred forty-seven".