243121131155 has 32 divisors (see below), whose sum is σ = 337572517248. Its totient is φ = 164647526400.

The previous prime is 243121131101. The next prime is 243121131181. The reversal of 243121131155 is 551131121342.

It is a happy number.

It is not a de Polignac number, because 243121131155 - 2¹⁴ = 243121114771 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1001975 + ... + 1220735.

It is an arithmetic number, because the mean of its divisors is an integer number (10549141164).

Almost surely, 2^243121131155 is an apocalyptic number.

243121131155 is a deficient number, since it is larger than the sum of its proper divisors (94451386093).

243121131155 is a wasteful number, since it uses less digits than its factorization.

243121131155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219167.

The product of its digits is 3600, while the sum is 29.

Adding to 243121131155 its reverse (551131121342), we get a palindrome (794252252497).

The spelling of 243121131155 in words is "two hundred forty-three billion, one hundred twenty-one million, one hundred thirty-one thousand, one hundred fifty-five".