243220189 has 2 divisors, whose sum is σ = 243220190. Its totient is φ = 243220188.

The previous prime is 243220099. The next prime is 243220199. The reversal of 243220189 is 981022342.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 239723289 + 3496900 = 15483^2 + 1870^2 .

It is a cyclic number.

It is not a de Polignac number, because 243220189 - 2¹⁷ = 243089117 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 243220189.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243220199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121610094 + 121610095.

It is an arithmetic number, because the mean of its divisors is an integer number (121610095).

Almost surely, 2^243220189 is an apocalyptic number.

It is an amenable number.

243220189 is a deficient number, since it is larger than the sum of its proper divisors (1).

243220189 is an equidigital number, since it uses as much as digits as its factorization.

243220189 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 243220189 is about 15595.5182344159. The cubic root of 243220189 is about 624.2135721450.

The spelling of 243220189 in words is "two hundred forty-three million, two hundred twenty thousand, one hundred eighty-nine".