243121233221 has 8 divisors (see below), whose sum is σ = 259150152600. Its totient is φ = 227284277248.

The previous prime is 243121233209. The next prime is 243121233227. The reversal of 243121233221 is 122332121342.

It can be written as a sum of positive squares in 4 ways, for example, as 757020196 + 242364213025 = 27514^2 + 492305^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 243121233221 - 2¹⁴ = 243121216837 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243121233227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47988236 + ... + 47993301.

It is an arithmetic number, because the mean of its divisors is an integer number (32393769075).

Almost surely, 2^243121233221 is an apocalyptic number.

It is an amenable number.

243121233221 is a deficient number, since it is larger than the sum of its proper divisors (16028919379).

243121233221 is a wasteful number, since it uses less digits than its factorization.

243121233221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95981703.

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

Adding to 243121233221 its reverse (122332121342), we get a palindrome (365453354563).

The spelling of 243121233221 in words is "two hundred forty-three billion, one hundred twenty-one million, two hundred thirty-three thousand, two hundred twenty-one".