243120355531 has 2 divisors, whose sum is σ = 243120355532. Its totient is φ = 243120355530.

The previous prime is 243120355481. The next prime is 243120355547. The reversal of 243120355531 is 135553021342.

243120355531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 243120355531 - 2⁷ = 243120355403 is a prime.

It is a super-2 number, since 2×243120355531² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (243120355571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121560177765 + 121560177766.

It is an arithmetic number, because the mean of its divisors is an integer number (121560177766).

Almost surely, 2^243120355531 is an apocalyptic number.

243120355531 is a deficient number, since it is larger than the sum of its proper divisors (1).

243120355531 is an equidigital number, since it uses as much as digits as its factorization.

243120355531 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 54000, while the sum is 34.

Adding to 243120355531 its reverse (135553021342), we get a palindrome (378673376873).

The spelling of 243120355531 in words is "two hundred forty-three billion, one hundred twenty million, three hundred fifty-five thousand, five hundred thirty-one".