221212322321 has 2 divisors, whose sum is σ = 221212322322. Its totient is φ = 221212322320.

The previous prime is 221212322291. The next prime is 221212322329. The reversal of 221212322321 is 123223212122.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 155835457600 + 65376864721 = 394760^2 + 255689^2 .

It is a cyclic number.

It is not a de Polignac number, because 221212322321 - 2¹⁸ = 221212060177 is a prime.

It is not a weakly prime, because it can be changed into another prime (221212322329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110606161160 + 110606161161.

It is an arithmetic number, because the mean of its divisors is an integer number (110606161161).

Almost surely, 2^221212322321 is an apocalyptic number.

It is an amenable number.

221212322321 is a deficient number, since it is larger than the sum of its proper divisors (1).

221212322321 is an equidigital number, since it uses as much as digits as its factorization.

221212322321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152, while the sum is 23.

Adding to 221212322321 its reverse (123223212122), we get a palindrome (344435534443).

The spelling of 221212322321 in words is "two hundred twenty-one billion, two hundred twelve million, three hundred twenty-two thousand, three hundred twenty-one".