243121 has 2 divisors, whose sum is σ = 243122.
Its totient is φ = 243120.
The previous prime is 243119. The next prime is 243137. The reversal of 243121 is 121342.
Adding to 243121 its reverse (121342), we get a palindrome (364463).
It can be divided in two parts, 243 and 121, that multiplied together give a triangular number (29403 = T242).
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 216225 + 26896 = 465^2 + 164^2
It is a cyclic number.
It is not a de Polignac number, because 243121 - 21 = 243119 is a prime.
Together with 243119, it forms a pair of twin primes.
It is a Chen prime.
It is a nialpdrome in base 12.
It is not a weakly prime, because it can be changed into another prime (243101) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (11) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121560 + 121561.
It is an arithmetic number, because the mean of its divisors is an integer number (121561).
2243121 is an apocalyptic number.
It is an amenable number.
243121 is a deficient number, since it is larger than the sum of its proper divisors (1).
243121 is an equidigital number, since it uses as much as digits as its factorization.
243121 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 48, while the sum is 13.
The square root of 243121 is about 493.0730169052.
The cubic root of 243121 is about 62.4128705919.
The spelling of 243121 in words is "two hundred forty-three thousand, one hundred twenty-one", and thus it is an iban number.