21120220022221 has 2 divisors, whose sum is σ = 21120220022222. Its totient is φ = 21120220022220.

The previous prime is 21120220022173. The next prime is 21120220022269. The reversal of 21120220022221 is 12222002202112.

It is a balanced prime because it is at equal distance from previous prime (21120220022173) and next prime (21120220022269).

It can be written as a sum of positive squares in only one way, i.e., 20731948965225 + 388271056996 = 4553235^2 + 623114^2 .

It is a cyclic number.

It is not a de Polignac number, because 21120220022221 - 2¹⁷ = 21120219891149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21120220022021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560110011110 + 10560110011111.

It is an arithmetic number, because the mean of its divisors is an integer number (10560110011111).

Almost surely, 2^{21120220022221} is an apocalyptic number.

It is an amenable number.

21120220022221 is a deficient number, since it is larger than the sum of its proper divisors (1).

21120220022221 is an equidigital number, since it uses as much as digits as its factorization.

21120220022221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 21120220022221 its reverse (12222002202112), we get a palindrome (33342222224333).

The spelling of 21120220022221 in words is "twenty-one trillion, one hundred twenty billion, two hundred twenty million, twenty-two thousand, two hundred twenty-one".