243243434522531 has 2 divisors, whose sum is σ = 243243434522532. Its totient is φ = 243243434522530.

The previous prime is 243243434522513. The next prime is 243243434522551. The reversal of 243243434522531 is 135225434342342.

It is a happy number.

243243434522531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with previous prime (243243434522513) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243243434522531 is a prime.

It is a super-2 number, since 2×243243434522531² (a number of 30 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (243243434522551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121621717261265 + 121621717261266.

It is an arithmetic number, because the mean of its divisors is an integer number (121621717261266).

Almost surely, 2^{243243434522531} is an apocalyptic number.

243243434522531 is a deficient number, since it is larger than the sum of its proper divisors (1).

243243434522531 is an equidigital number, since it uses as much as digits as its factorization.

243243434522531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8294400, while the sum is 47.

Adding to 243243434522531 its reverse (135225434342342), we get a palindrome (378468868864873).

The spelling of 243243434522531 in words is "two hundred forty-three trillion, two hundred forty-three billion, four hundred thirty-four million, five hundred twenty-two thousand, five hundred thirty-one".