22001212112221 has 2 divisors, whose sum is σ = 22001212112222. Its totient is φ = 22001212112220.

The previous prime is 22001212112147. The next prime is 22001212112233. The reversal of 22001212112221 is 12221121210022.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18751160328121 + 3250051784100 = 4330261^2 + 1802790^2 .

It is a cyclic number.

It is not a de Polignac number, because 22001212112221 - 2²³ = 22001203723613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22001212112291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11000606056110 + 11000606056111.

It is an arithmetic number, because the mean of its divisors is an integer number (11000606056111).

Almost surely, 2^{22001212112221} is an apocalyptic number.

It is an amenable number.

22001212112221 is a deficient number, since it is larger than the sum of its proper divisors (1).

22001212112221 is an equidigital number, since it uses as much as digits as its factorization.

22001212112221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 22001212112221 its reverse (12221121210022), we get a palindrome (34222333322243).

The spelling of 22001212112221 in words is "twenty-two trillion, one billion, two hundred twelve million, one hundred twelve thousand, two hundred twenty-one".