212221109909 has 2 divisors, whose sum is σ = 212221109910. Its totient is φ = 212221109908.

The previous prime is 212221109897. The next prime is 212221109941. The reversal of 212221109909 is 909901122212.

It is a happy number.

212221109909 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 211763791684 + 457318225 = 460178^2 + 21385^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212221109909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212221109959) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106110554954 + 106110554955.

It is an arithmetic number, because the mean of its divisors is an integer number (106110554955).

Almost surely, 2^212221109909 is an apocalyptic number.

It is an amenable number.

212221109909 is a deficient number, since it is larger than the sum of its proper divisors (1).

212221109909 is an equidigital number, since it uses as much as digits as its factorization.

212221109909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 38.

The spelling of 212221109909 in words is "two hundred twelve billion, two hundred twenty-one million, one hundred nine thousand, nine hundred nine".