243997769 has 2 divisors, whose sum is σ = 243997770. Its totient is φ = 243997768.

The previous prime is 243997763. The next prime is 243997811. The reversal of 243997769 is 967799342.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 153462544 + 90535225 = 12388^2 + 9515^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243997769 is a prime.

It is a super-2 number, since 2×243997769² = 119069822553954722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (243997763) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121998884 + 121998885.

It is an arithmetic number, because the mean of its divisors is an integer number (121998885).

Almost surely, 2^243997769 is an apocalyptic number.

It is an amenable number.

243997769 is a deficient number, since it is larger than the sum of its proper divisors (1).

243997769 is an equidigital number, since it uses as much as digits as its factorization.

243997769 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5143824, while the sum is 56.

The square root of 243997769 is about 15620.4279390803. The cubic root of 243997769 is about 624.8780724287.

The spelling of 243997769 in words is "two hundred forty-three million, nine hundred ninety-seven thousand, seven hundred sixty-nine".