12231312221 has 2 divisors, whose sum is σ = 12231312222. Its totient is φ = 12231312220.

The previous prime is 12231312217. The next prime is 12231312227. The reversal of 12231312221 is 12221313221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8857444996 + 3373867225 = 94114^2 + 58085^2 .

It is a cyclic number.

It is not a de Polignac number, because 12231312221 - 2² = 12231312217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12231312193 and 12231312202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12231312227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6115656110 + 6115656111.

It is an arithmetic number, because the mean of its divisors is an integer number (6115656111).

Almost surely, 2^12231312221 is an apocalyptic number.

It is an amenable number.

12231312221 is a deficient number, since it is larger than the sum of its proper divisors (1).

12231312221 is an equidigital number, since it uses as much as digits as its factorization.

12231312221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 288, while the sum is 20.

Adding to 12231312221 its reverse (12221313221), we get a palindrome (24452625442).

The spelling of 12231312221 in words is "twelve billion, two hundred thirty-one million, three hundred twelve thousand, two hundred twenty-one".