243726869 has 2 divisors, whose sum is σ = 243726870. Its totient is φ = 243726868.

The previous prime is 243726863. The next prime is 243726871. The reversal of 243726869 is 968627342.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 239104369 + 4622500 = 15463^2 + 2150^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243726869 is a prime.

It is a super-2 number, since 2×243726869² = 118805573345086322, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 243726871, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243726863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121863434 + 121863435.

It is an arithmetic number, because the mean of its divisors is an integer number (121863435).

Almost surely, 2^243726869 is an apocalyptic number.

It is an amenable number.

243726869 is a deficient number, since it is larger than the sum of its proper divisors (1).

243726869 is an equidigital number, since it uses as much as digits as its factorization.

243726869 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 870912, while the sum is 47.

The square root of 243726869 is about 15611.7541935556. The cubic root of 243726869 is about 624.6467285698.

The spelling of 243726869 in words is "two hundred forty-three million, seven hundred twenty-six thousand, eight hundred sixty-nine".