243404312121 has 32 divisors (see below), whose sum is σ = 382157637120. Its totient is φ = 152585494272.

The previous prime is 243404312113. The next prime is 243404312141. The reversal of 243404312121 is 121213404342.

243404312121 is a `hidden beast` number, since 2 + 4 + 340 + 4 + 312 + 1 + 2 + 1 = 666.

It is not a de Polignac number, because 243404312121 - 2³ = 243404312113 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (243404312141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 265891 + ... + 746663.

It is an arithmetic number, because the mean of its divisors is an integer number (11942426160).

Almost surely, 2^243404312121 is an apocalyptic number.

It is an amenable number.

243404312121 is a deficient number, since it is larger than the sum of its proper divisors (138753324999).

243404312121 is a wasteful number, since it uses less digits than its factorization.

243404312121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 481902 (or 481896 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

Adding to 243404312121 its reverse (121213404342), we get a palindrome (364617716463).

The spelling of 243404312121 in words is "two hundred forty-three billion, four hundred four million, three hundred twelve thousand, one hundred twenty-one".