20211221120221 has 8 divisors (see below), whose sum is σ = 21400171398144. Its totient is φ = 19022276944320.

The previous prime is 20211221120219. The next prime is 20211221120243. The reversal of 20211221120221 is 12202112211202.

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 20211221120221 - 2¹ = 20211221120219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20211221120201) 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, 6500196 + ... + 9092578.

It is an arithmetic number, because the mean of its divisors is an integer number (2675021424768).

Almost surely, 2^{20211221120221} is an apocalyptic number.

It is an amenable number.

20211221120221 is a deficient number, since it is larger than the sum of its proper divisors (1188950277923).

20211221120221 is a wasteful number, since it uses less digits than its factorization.

20211221120221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3051011.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 20211221120221 its reverse (12202112211202), we get a palindrome (32413333331423).

The spelling of 20211221120221 in words is "twenty trillion, two hundred eleven billion, two hundred twenty-one million, one hundred twenty thousand, two hundred twenty-one".