21222001210121 has 4 divisors (see below), whose sum is σ = 21222135043200. Its totient is φ = 21221867377044.

The previous prime is 21222001210079. The next prime is 21222001210139. The reversal of 21222001210121 is 12101210022212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21222001210121 - 2¹⁸ = 21222000947977 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21222001210121.

It is not an unprimeable number, because it can be changed into a prime (21222001219121) 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 3 ways as a sum of consecutive naturals, for example, 66678401 + ... + 66995918.

It is an arithmetic number, because the mean of its divisors is an integer number (5305533760800).

Almost surely, 2^{21222001210121} is an apocalyptic number.

It is an amenable number.

21222001210121 is a deficient number, since it is larger than the sum of its proper divisors (133833079).

21222001210121 is a wasteful number, since it uses less digits than its factorization.

21222001210121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133833078.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21222001210121 its reverse (12101210022212), we get a palindrome (33323211232333).

The spelling of 21222001210121 in words is "twenty-one trillion, two hundred twenty-two billion, one million, two hundred ten thousand, one hundred twenty-one".