243513879209 has 2 divisors, whose sum is σ = 243513879210. Its totient is φ = 243513879208.

The previous prime is 243513879181. The next prime is 243513879233. The reversal of 243513879209 is 902978315342.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 122111808025 + 121402071184 = 349445^2 + 348428^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243513879209 is a prime.

It is not a weakly prime, because it can be changed into another prime (243513879109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121756939604 + 121756939605.

It is an arithmetic number, because the mean of its divisors is an integer number (121756939605).

Almost surely, 2^243513879209 is an apocalyptic number.

It is an amenable number.

243513879209 is a deficient number, since it is larger than the sum of its proper divisors (1).

243513879209 is an equidigital number, since it uses as much as digits as its factorization.

243513879209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3265920, while the sum is 53.

The spelling of 243513879209 in words is "two hundred forty-three billion, five hundred thirteen million, eight hundred seventy-nine thousand, two hundred nine".