21212021212201 has 2 divisors, whose sum is σ = 21212021212202. Its totient is φ = 21212021212200.

The previous prime is 21212021212183. The next prime is 21212021212223. The reversal of 21212021212201 is 10221212021212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21212021133801 + 78400 = 4605651^2 + 280^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212021212201 - 2⁷ = 21212021212073 is a prime.

It is not a weakly prime, because it can be changed into another prime (21212021212301) 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, 10606010606100 + 10606010606101.

It is an arithmetic number, because the mean of its divisors is an integer number (10606010606101).

Almost surely, 2^{21212021212201} is an apocalyptic number.

It is an amenable number.

21212021212201 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212021212201 is an equidigital number, since it uses as much as digits as its factorization.

21212021212201 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 21212021212201 its reverse (10221212021212), we get a palindrome (31433233233413).

The spelling of 21212021212201 in words is "twenty-one trillion, two hundred twelve billion, twenty-one million, two hundred twelve thousand, two hundred one".