243344321021 has 4 divisors (see below), whose sum is σ = 243566149212. Its totient is φ = 243122492832.

The previous prime is 243344321009. The next prime is 243344321029. The reversal of 243344321021 is 120123443342.

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 53933095225 + 189411225796 = 232235^2 + 435214^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243344321021 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 (243344321029) 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, 110912450 + ... + 110914643.

It is an arithmetic number, because the mean of its divisors is an integer number (60891537303).

Almost surely, 2^243344321021 is an apocalyptic number.

It is an amenable number.

243344321021 is a deficient number, since it is larger than the sum of its proper divisors (221828191).

243344321021 is a wasteful number, since it uses less digits than its factorization.

243344321021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221828190.

The product of its (nonzero) digits is 13824, while the sum is 29.

Adding to 243344321021 its reverse (120123443342), we get a palindrome (363467764363).

The spelling of 243344321021 in words is "two hundred forty-three billion, three hundred forty-four million, three hundred twenty-one thousand, twenty-one".