21231331121 has 32 divisors (see below), whose sum is σ = 28654364928. Its totient is φ = 15192023040.

The previous prime is 21231331081. The next prime is 21231331123. The reversal of 21231331121 is 12113313212.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21231331121 - 2³⁰ = 20157589297 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21231331093 and 21231331102.

It is not an unprimeable number, because it can be changed into a prime (21231331123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 138245 + ... + 248141.

It is an arithmetic number, because the mean of its divisors is an integer number (895448904).

Almost surely, 2^21231331121 is an apocalyptic number.

It is an amenable number.

21231331121 is a deficient number, since it is larger than the sum of its proper divisors (7423033807).

21231331121 is a wasteful number, since it uses less digits than its factorization.

21231331121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110121.

The product of its digits is 216, while the sum is 20.

Adding to 21231331121 its reverse (12113313212), we get a palindrome (33344644333).

The spelling of 21231331121 in words is "twenty-one billion, two hundred thirty-one million, three hundred thirty-one thousand, one hundred twenty-one".