243121530505 has 16 divisors (see below), whose sum is σ = 333826053120. Its totient is φ = 166510786752.

The previous prime is 243121530499. The next prime is 243121530557. The reversal of 243121530505 is 505035121342.

It is a cyclic number.

It is not a de Polignac number, because 243121530505 - 2⁵ = 243121530473 is a prime.

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, 4160569 + ... + 4218598.

It is an arithmetic number, because the mean of its divisors is an integer number (20864128320).

Almost surely, 2^243121530505 is an apocalyptic number.

It is an amenable number.

243121530505 is a deficient number, since it is larger than the sum of its proper divisors (90704522615).

243121530505 is an equidigital number, since it uses as much as digits as its factorization.

243121530505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8380008.

The product of its (nonzero) digits is 18000, while the sum is 31.

Adding to 243121530505 its reverse (505035121342), we get a palindrome (748156651847).

The spelling of 243121530505 in words is "two hundred forty-three billion, one hundred twenty-one million, five hundred thirty thousand, five hundred five".