243121304431 has 4 divisors (see below), whose sum is σ = 253691795952. Its totient is φ = 232550812912.

The previous prime is 243121304429. The next prime is 243121304467. The reversal of 243121304431 is 134403121342.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 243121304431 - 2¹ = 243121304429 is a prime.

It is a super-2 number, since 2×243121304431² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 243121304431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243121304401) 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, 5285245726 + ... + 5285245771.

It is an arithmetic number, because the mean of its divisors is an integer number (63422948988).

Almost surely, 2^243121304431 is an apocalyptic number.

243121304431 is a deficient number, since it is larger than the sum of its proper divisors (10570491521).

243121304431 is a wasteful number, since it uses less digits than its factorization.

243121304431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10570491520.

The product of its (nonzero) digits is 6912, while the sum is 28.

Adding to 243121304431 its reverse (134403121342), we get a palindrome (377524425773).

The spelling of 243121304431 in words is "two hundred forty-three billion, one hundred twenty-one million, three hundred four thousand, four hundred thirty-one".