243723661567 has 2 divisors, whose sum is σ = 243723661568. Its totient is φ = 243723661566.

The previous prime is 243723661529. The next prime is 243723661663. The reversal of 243723661567 is 765166327342.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243723661567 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243723661967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121861830783 + 121861830784.

It is an arithmetic number, because the mean of its divisors is an integer number (121861830784).

Almost surely, 2^243723661567 is an apocalyptic number.

243723661567 is a deficient number, since it is larger than the sum of its proper divisors (1).

243723661567 is an equidigital number, since it uses as much as digits as its factorization.

243723661567 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7620480, while the sum is 52.

The spelling of 243723661567 in words is "two hundred forty-three billion, seven hundred twenty-three million, six hundred sixty-one thousand, five hundred sixty-seven".