243042555505 has 4 divisors (see below), whose sum is σ = 291651066612. Its totient is φ = 194434044400.

The previous prime is 243042555463. The next prime is 243042555523. The reversal of 243042555505 is 505555240342.

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 163513479424 + 79529076081 = 404368^2 + 282009^2 .

It is not a de Polignac number, because 243042555505 - 2⁷ = 243042555377 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24304255546 + ... + 24304255555.

It is an arithmetic number, because the mean of its divisors is an integer number (72912766653).

Almost surely, 2^243042555505 is an apocalyptic number.

It is an amenable number.

243042555505 is a deficient number, since it is larger than the sum of its proper divisors (48608511107).

243042555505 is an equidigital number, since it uses as much as digits as its factorization.

243042555505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48608511106.

The product of its (nonzero) digits is 600000, while the sum is 40.

Adding to 243042555505 its reverse (505555240342), we get a palindrome (748597795847).

The spelling of 243042555505 in words is "two hundred forty-three billion, forty-two million, five hundred fifty-five thousand, five hundred five".