243997423 has 2 divisors, whose sum is σ = 243997424. Its totient is φ = 243997422.

The previous prime is 243997399. The next prime is 243997433. The reversal of 243997423 is 324799342.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 243997423 - 2¹⁷ = 243866351 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 243997423.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243997433) 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, 121998711 + 121998712.

It is an arithmetic number, because the mean of its divisors is an integer number (121998712).

Almost surely, 2^243997423 is an apocalyptic number.

243997423 is a deficient number, since it is larger than the sum of its proper divisors (1).

243997423 is an equidigital number, since it uses as much as digits as its factorization.

243997423 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 326592, while the sum is 43.

The square root of 243997423 is about 15620.4168638356. The cubic root of 243997423 is about 624.8777770600.

The spelling of 243997423 in words is "two hundred forty-three million, nine hundred ninety-seven thousand, four hundred twenty-three".