21022001120221 has 8 divisors (see below), whose sum is σ = 21137872671864. Its totient is φ = 20906201210880.

The previous prime is 21022001120161. The next prime is 21022001120227. The reversal of 21022001120221 is 12202110022012.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 2427320376196 + 18594680744025 = 1557986^2 + 4312155^2 .

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 21022001120221 - 2⁷ = 21022001120093 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21022001120195 and 21022001120204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21022001120227) 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, 17322046 + ... + 18495871.

It is an arithmetic number, because the mean of its divisors is an integer number (2642234083983).

Almost surely, 2^{21022001120221} is an apocalyptic number.

It is an amenable number.

21022001120221 is a deficient number, since it is larger than the sum of its proper divisors (115871551643).

21022001120221 is a wasteful number, since it uses less digits than its factorization.

21022001120221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35821151.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21022001120221 its reverse (12202110022012), we get a palindrome (33224111142233).

The spelling of 21022001120221 in words is "twenty-one trillion, twenty-two billion, one million, one hundred twenty thousand, two hundred twenty-one".