131005223221 has 2 divisors, whose sum is σ = 131005223222. Its totient is φ = 131005223220.

The previous prime is 131005223197. The next prime is 131005223243. The reversal of 131005223221 is 122322500131.

It is an a-pointer prime, because the next prime (131005223243) can be obtained adding 131005223221 to its sum of digits (22).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 69743528100 + 61261695121 = 264090^2 + 247511^2 .

It is a cyclic number.

It is not a de Polignac number, because 131005223221 - 2⁷ = 131005223093 is a prime.

It is a super-2 number, since 2×131005223221² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 131005223192 and 131005223201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131005223281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65502611610 + 65502611611.

It is an arithmetic number, because the mean of its divisors is an integer number (65502611611).

Almost surely, 2^131005223221 is an apocalyptic number.

It is an amenable number.

131005223221 is a deficient number, since it is larger than the sum of its proper divisors (1).

131005223221 is an equidigital number, since it uses as much as digits as its factorization.

131005223221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720, while the sum is 22.

Adding to 131005223221 its reverse (122322500131), we get a palindrome (253327723352).

The spelling of 131005223221 in words is "one hundred thirty-one billion, five million, two hundred twenty-three thousand, two hundred twenty-one".