243384821 has 2 divisors, whose sum is σ = 243384822. Its totient is φ = 243384820.

The previous prime is 243384797. The next prime is 243384863. The reversal of 243384821 is 128483342.

243384821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 201924100 + 41460721 = 14210^2 + 6439^2 .

It is a cyclic number.

It is not a de Polignac number, because 243384821 - 2¹⁰ = 243383797 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243384881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121692410 + 121692411.

It is an arithmetic number, because the mean of its divisors is an integer number (121692411).

Almost surely, 2^243384821 is an apocalyptic number.

It is an amenable number.

243384821 is a deficient number, since it is larger than the sum of its proper divisors (1).

243384821 is an equidigital number, since it uses as much as digits as its factorization.

243384821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36864, while the sum is 35.

The square root of 243384821 is about 15600.7955245878. The cubic root of 243384821 is about 624.3543805638.

The spelling of 243384821 in words is "two hundred forty-three million, three hundred eighty-four thousand, eight hundred twenty-one".