21212220220189 has 2 divisors, whose sum is σ = 21212220220190. Its totient is φ = 21212220220188.

The previous prime is 21212220220151. The next prime is 21212220220259. The reversal of 21212220220189 is 98102202221212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21067319707225 + 144900512964 = 4589915^2 + 380658^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212220220189 - 2²³ = 21212211831581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21212220220129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606110110094 + 10606110110095.

It is an arithmetic number, because the mean of its divisors is an integer number (10606110110095).

Almost surely, 2^{21212220220189} is an apocalyptic number.

It is an amenable number.

21212220220189 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212220220189 is an equidigital number, since it uses as much as digits as its factorization.

21212220220189 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9216, while the sum is 34.

The spelling of 21212220220189 in words is "twenty-one trillion, two hundred twelve billion, two hundred twenty million, two hundred twenty thousand, one hundred eighty-nine".