131243241221 has 4 divisors (see below), whose sum is σ = 131245536012. Its totient is φ = 131240946432.

The previous prime is 131243241191. The next prime is 131243241223. The reversal of 131243241221 is 122142342131.

It is a happy number.

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 41251641025 + 89991600196 = 203105^2 + 299986^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-131243241221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131243241223) 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, 1059356 + ... + 1176741.

It is an arithmetic number, because the mean of its divisors is an integer number (32811384003).

Almost surely, 2^131243241221 is an apocalyptic number.

It is an amenable number.

131243241221 is a deficient number, since it is larger than the sum of its proper divisors (2294791).

131243241221 is an equidigital number, since it uses as much as digits as its factorization.

131243241221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2294790.

The product of its digits is 2304, while the sum is 26.

Adding to 131243241221 its reverse (122142342131), we get a palindrome (253385583352).

The spelling of 131243241221 in words is "one hundred thirty-one billion, two hundred forty-three million, two hundred forty-one thousand, two hundred twenty-one".