243121021530 has 32 divisors (see below), whose sum is σ = 584678858688. Its totient is φ = 64700227200.

The previous prime is 243121021513. The next prime is 243121021543. The reversal of 243121021530 is 35120121342.

It is a super-2 number, since 2×243121021530² (a number of 24 digits) contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 243121021530.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 8237851 + ... + 8267310.

It is an arithmetic number, because the mean of its divisors is an integer number (18271214334).

Almost surely, 2^243121021530 is an apocalyptic number.

243121021530 is an abundant number, since it is smaller than the sum of its proper divisors (341557837158).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

243121021530 is a wasteful number, since it uses less digits than its factorization.

243121021530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16505662.

The product of its (nonzero) digits is 1440, while the sum is 24.

Adding to 243121021530 its reverse (35120121342), we get a palindrome (278241142872).

The spelling of 243121021530 in words is "two hundred forty-three billion, one hundred twenty-one million, twenty-one thousand, five hundred thirty".