243204121 has 8 divisors (see below), whose sum is σ = 256339080. Its totient is φ = 230385792.

The previous prime is 243204119. The next prime is 243204151. The reversal of 243204121 is 121402342.

It can be written as a sum of positive squares in 4 ways, for example, as 95824521 + 147379600 = 9789^2 + 12140^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 243204121 - 2¹ = 243204119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (243204151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 77580 + ... + 80653.

It is an arithmetic number, because the mean of its divisors is an integer number (32042385).

Almost surely, 2^243204121 is an apocalyptic number.

It is an amenable number.

243204121 is a deficient number, since it is larger than the sum of its proper divisors (13134959).

243204121 is a wasteful number, since it uses less digits than its factorization.

243204121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158315.

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 243204121 is about 15595.0030779093. The cubic root of 243204121 is about 624.1998259115.

Adding to 243204121 its reverse (121402342), we get a palindrome (364606463).

It can be divided in two parts, 24320 and 4121, that added together give a triangular number (28441 = T₂₃₈).

The spelling of 243204121 in words is "two hundred forty-three million, two hundred four thousand, one hundred twenty-one".