11531331121 has 4 divisors (see below), whose sum is σ = 11534095972. Its totient is φ = 11528566272.

The previous prime is 11531331109. The next prime is 11531331157. The reversal of 11531331121 is 12113313511.

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 6251274225 + 5280056896 = 79065^2 + 72664^2 .

It is a cyclic number.

It is not a de Polignac number, because 11531331121 - 2¹⁵ = 11531298353 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11531331092 and 11531331101.

It is not an unprimeable number, because it can be changed into a prime (11531335121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1376160 + ... + 1384513.

It is an arithmetic number, because the mean of its divisors is an integer number (2883523993).

Almost surely, 2^11531331121 is an apocalyptic number.

It is an amenable number.

11531331121 is a deficient number, since it is larger than the sum of its proper divisors (2764851).

11531331121 is an equidigital number, since it uses as much as digits as its factorization.

11531331121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2764850.

The product of its digits is 270, while the sum is 22.

Adding to 11531331121 its reverse (12113313511), we get a palindrome (23644644632).

The spelling of 11531331121 in words is "eleven billion, five hundred thirty-one million, three hundred thirty-one thousand, one hundred twenty-one".