131223132221 has 2 divisors, whose sum is σ = 131223132222. Its totient is φ = 131223132220.

The previous prime is 131223132203. The next prime is 131223132247. The reversal of 131223132221 is 122231322131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 120833407321 + 10389724900 = 347611^2 + 101930^2 .

It is a cyclic number.

It is not a de Polignac number, because 131223132221 - 2²⁶ = 131156023357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131223132251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65611566110 + 65611566111.

It is an arithmetic number, because the mean of its divisors is an integer number (65611566111).

Almost surely, 2^131223132221 is an apocalyptic number.

It is an amenable number.

131223132221 is a deficient number, since it is larger than the sum of its proper divisors (1).

131223132221 is an equidigital number, since it uses as much as digits as its factorization.

131223132221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864, while the sum is 23.

Adding to 131223132221 its reverse (122231322131), we get a palindrome (253454454352).

The spelling of 131223132221 in words is "one hundred thirty-one billion, two hundred twenty-three million, one hundred thirty-two thousand, two hundred twenty-one".