12131541221 has 4 divisors (see below), whose sum is σ = 12160495200. Its totient is φ = 12102587244.

The previous prime is 12131541217. The next prime is 12131541229. The reversal of 12131541221 is 12214513121.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12214513121 = 3023 ⋅4040527.

It is a cyclic number.

It is not a de Polignac number, because 12131541221 - 2² = 12131541217 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12131541229) 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, 14476361 + ... + 14477198.

It is an arithmetic number, because the mean of its divisors is an integer number (3040123800).

Almost surely, 2^12131541221 is an apocalyptic number.

It is an amenable number.

12131541221 is a deficient number, since it is larger than the sum of its proper divisors (28953979).

12131541221 is an equidigital number, since it uses as much as digits as its factorization.

12131541221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28953978.

The product of its digits is 480, while the sum is 23.

The spelling of 12131541221 in words is "twelve billion, one hundred thirty-one million, five hundred forty-one thousand, two hundred twenty-one".