243131442121 has 2 divisors, whose sum is σ = 243131442122. Its totient is φ = 243131442120.

The previous prime is 243131442107. The next prime is 243131442131. The reversal of 243131442121 is 121244131342.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 200627847225 + 42503594896 = 447915^2 + 206164^2 .

It is a cyclic number.

It is not a de Polignac number, because 243131442121 - 2²⁵ = 243097887689 is a prime.

It is a super-2 number, since 2×243131442121² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 243131442121.

It is not a weakly prime, because it can be changed into another prime (243131442131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121565721060 + 121565721061.

It is an arithmetic number, because the mean of its divisors is an integer number (121565721061).

Almost surely, 2^243131442121 is an apocalyptic number.

It is an amenable number.

243131442121 is a deficient number, since it is larger than the sum of its proper divisors (1).

243131442121 is an equidigital number, since it uses as much as digits as its factorization.

243131442121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 28.

Adding to 243131442121 its reverse (121244131342), we get a palindrome (364375573463).

The spelling of 243131442121 in words is "two hundred forty-three billion, one hundred thirty-one million, four hundred forty-two thousand, one hundred twenty-one".