243112109 has 2 divisors, whose sum is σ = 243112110. Its totient is φ = 243112108.

The previous prime is 243112091. The next prime is 243112157. The reversal of 243112109 is 901211342.

Together with previous prime (243112091) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 243048100 + 64009 = 15590^2 + 253^2 .

It is a cyclic number.

It is not a de Polignac number, because 243112109 - 2²⁴ = 226334893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243112169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121556054 + 121556055.

It is an arithmetic number, because the mean of its divisors is an integer number (121556055).

Almost surely, 2^243112109 is an apocalyptic number.

It is an amenable number.

243112109 is a deficient number, since it is larger than the sum of its proper divisors (1).

243112109 is an equidigital number, since it uses as much as digits as its factorization.

243112109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 243112109 is about 15592.0527513217. The cubic root of 243112109 is about 624.1210976417.

The spelling of 243112109 in words is "two hundred forty-three million, one hundred twelve thousand, one hundred nine".