243121245355 has 4 divisors (see below), whose sum is σ = 291745494432. Its totient is φ = 194496996280.

The previous prime is 243121245347. The next prime is 243121245397. The reversal of 243121245355 is 553542121342.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 243121245355 - 2³ = 243121245347 is a prime.

It is a super-3 number, since 3×243121245355³ (a number of 35 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

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, 24312124531 + ... + 24312124540.

It is an arithmetic number, because the mean of its divisors is an integer number (72936373608).

Almost surely, 2^243121245355 is an apocalyptic number.

243121245355 is a deficient number, since it is larger than the sum of its proper divisors (48624249077).

243121245355 is an equidigital number, since it uses as much as digits as its factorization.

243121245355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48624249076.

The product of its digits is 144000, while the sum is 37.

Adding to 243121245355 its reverse (553542121342), we get a palindrome (796663366697).

The spelling of 243121245355 in words is "two hundred forty-three billion, one hundred twenty-one million, two hundred forty-five thousand, three hundred fifty-five".