243689908249 has 2 divisors, whose sum is σ = 243689908250. Its totient is φ = 243689908248.

The previous prime is 243689908183. The next prime is 243689908283. The reversal of 243689908249 is 942809986342.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 243127886400 + 562021849 = 493080^2 + 23707^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243689908249 is a prime.

It is not a weakly prime, because it can be changed into another prime (243689908289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121844954124 + 121844954125.

It is an arithmetic number, because the mean of its divisors is an integer number (121844954125).

Almost surely, 2^243689908249 is an apocalyptic number.

It is an amenable number.

243689908249 is a deficient number, since it is larger than the sum of its proper divisors (1).

243689908249 is an equidigital number, since it uses as much as digits as its factorization.

243689908249 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 53747712, while the sum is 64.

The spelling of 243689908249 in words is "two hundred forty-three billion, six hundred eighty-nine million, nine hundred eight thousand, two hundred forty-nine".