243121234505 has 16 divisors (see below), whose sum is σ = 304735841280. Its totient is φ = 185966977728.

The previous prime is 243121234441. The next prime is 243121234507. The reversal of 243121234505 is 505432121342.

It is a cyclic number.

It is not a de Polignac number, because 243121234505 - 2⁶ = 243121234441 is a prime.

It is not an unprimeable number, because it can be changed into a prime (243121234507) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8124377 + ... + 8154246.

It is an arithmetic number, because the mean of its divisors is an integer number (19045990080).

Almost surely, 2^243121234505 is an apocalyptic number.

It is an amenable number.

243121234505 is a deficient number, since it is larger than the sum of its proper divisors (61614606775).

243121234505 is a wasteful number, since it uses less digits than its factorization.

243121234505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16278760.

The product of its (nonzero) digits is 28800, while the sum is 32.

Adding to 243121234505 its reverse (505432121342), we get a palindrome (748553355847).

The spelling of 243121234505 in words is "two hundred forty-three billion, one hundred twenty-one million, two hundred thirty-four thousand, five hundred five".