243312212321 has 4 divisors (see below), whose sum is σ = 243684819732. Its totient is φ = 242939604912.

The previous prime is 243312212303. The next prime is 243312212357. The reversal of 243312212321 is 123212213342.

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 95521174225 + 147791038096 = 309065^2 + 384436^2 .

It is a cyclic number.

It is not a de Polignac number, because 243312212321 - 2¹⁴ = 243312195937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (243312212371) 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, 186302726 + ... + 186304031.

It is an arithmetic number, because the mean of its divisors is an integer number (60921204933).

Almost surely, 2^243312212321 is an apocalyptic number.

It is an amenable number.

243312212321 is a deficient number, since it is larger than the sum of its proper divisors (372607411).

243312212321 is an equidigital number, since it uses as much as digits as its factorization.

243312212321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 372607410.

The product of its digits is 3456, while the sum is 26.

Adding to 243312212321 its reverse (123212213342), we get a palindrome (366524425663).

The spelling of 243312212321 in words is "two hundred forty-three billion, three hundred twelve million, two hundred twelve thousand, three hundred twenty-one".