243443121 has 4 divisors (see below), whose sum is σ = 324590832. Its totient is φ = 162295412.

The previous prime is 243443113. The next prime is 243443141. The reversal of 243443121 is 121344342.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 243443121 - 2³ = 243443113 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 243443091 and 243443100.

It is not an unprimeable number, because it can be changed into a prime (243443141) 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 3 ways as a sum of consecutive naturals, for example, 40573851 + ... + 40573856.

It is an arithmetic number, because the mean of its divisors is an integer number (81147708).

Almost surely, 2^243443121 is an apocalyptic number.

It is an amenable number.

243443121 is a deficient number, since it is larger than the sum of its proper divisors (81147711).

243443121 is an equidigital number, since it uses as much as digits as its factorization.

243443121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81147710.

The product of its digits is 2304, while the sum is 24.

The square root of 243443121 is about 15602.6639071666. The cubic root of 243443121 is about 624.4042288579.

Adding to 243443121 its sum of digits (24), we get a triangular number (243443145 = T₂₂₀₆₅).

Adding to 243443121 its reverse (121344342), we get a palindrome (364787463).

The spelling of 243443121 in words is "two hundred forty-three million, four hundred forty-three thousand, one hundred twenty-one".