21212220220001 has 8 divisors (see below), whose sum is σ = 21379395901440. Its totient is φ = 21045046887648.

The previous prime is 21212220219973. The next prime is 21212220220007. The reversal of 21212220220001 is 10002202221212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21212220220001 - 2¹⁰ = 21212220218977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21212220220007) 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 in 7 ways as a sum of consecutive naturals, for example, 20521565 + ... + 21530421.

It is an arithmetic number, because the mean of its divisors is an integer number (2672424487680).

Almost surely, 2^{21212220220001} is an apocalyptic number.

It is an amenable number.

21212220220001 is a deficient number, since it is larger than the sum of its proper divisors (167175681439).

21212220220001 is a wasteful number, since it uses less digits than its factorization.

21212220220001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1174543.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21212220220001 its reverse (10002202221212), we get a palindrome (31214422441213).

The spelling of 21212220220001 in words is "twenty-one trillion, two hundred twelve billion, two hundred twenty million, two hundred twenty thousand, one".