243111431021 has 4 divisors (see below), whose sum is σ = 257412103452. Its totient is φ = 228810758592.

The previous prime is 243111430993. The next prime is 243111431051. The reversal of 243111431021 is 120134111342.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 145095475396 + 98015955625 = 380914^2 + 313075^2 .

It is a cyclic number.

It is not a de Polignac number, because 243111431021 - 2¹⁸ = 243111168877 is a prime.

It is a super-2 number, since 2×243111431021² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243111431051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7150336190 + ... + 7150336223.

It is an arithmetic number, because the mean of its divisors is an integer number (64353025863).

Almost surely, 2^243111431021 is an apocalyptic number.

It is an amenable number.

243111431021 is a deficient number, since it is larger than the sum of its proper divisors (14300672431).

243111431021 is a wasteful number, since it uses less digits than its factorization.

243111431021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14300672430.

The product of its (nonzero) digits is 576, while the sum is 23.

Adding to 243111431021 its reverse (120134111342), we get a palindrome (363245542363).

The spelling of 243111431021 in words is "two hundred forty-three billion, one hundred eleven million, four hundred thirty-one thousand, twenty-one".