243042161 has 2 divisors, whose sum is σ = 243042162. Its totient is φ = 243042160.

The previous prime is 243042119. The next prime is 243042169. The reversal of 243042161 is 161240342.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 171741025 + 71301136 = 13105^2 + 8444^2 .

It is a cyclic number.

It is not a de Polignac number, because 243042161 - 2⁶ = 243042097 is a prime.

It is equal to p_13319042 and since 243042161 and 13319042 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (243042169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121521080 + 121521081.

It is an arithmetic number, because the mean of its divisors is an integer number (121521081).

Almost surely, 2^243042161 is an apocalyptic number.

It is an amenable number.

243042161 is a deficient number, since it is larger than the sum of its proper divisors (1).

243042161 is an equidigital number, since it uses as much as digits as its factorization.

243042161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 243042161 is about 15589.8095241732. The cubic root of 243042161 is about 624.0612347109.

The spelling of 243042161 in words is "two hundred forty-three million, forty-two thousand, one hundred sixty-one".