11231431121 has 4 divisors (see below), whose sum is σ = 11231852544. Its totient is φ = 11231009700.

The previous prime is 11231431109. The next prime is 11231431129. The reversal of 11231431121 is 12113413211.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11231431121 is a prime.

It is a super-2 number, since 2×11231431121² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 11231431093 and 11231431102.

It is not an unprimeable number, because it can be changed into a prime (11231431129) 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, 167825 + ... + 225006.

It is an arithmetic number, because the mean of its divisors is an integer number (2807963136).

Almost surely, 2^11231431121 is an apocalyptic number.

It is an amenable number.

11231431121 is a deficient number, since it is larger than the sum of its proper divisors (421423).

11231431121 is an equidigital number, since it uses as much as digits as its factorization.

11231431121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 421422.

The product of its digits is 144, while the sum is 20.

Adding to 11231431121 its reverse (12113413211), we get a palindrome (23344844332).

The spelling of 11231431121 in words is "eleven billion, two hundred thirty-one million, four hundred thirty-one thousand, one hundred twenty-one".