20211221210022 has 48 divisors (see below), whose sum is σ = 46195326927360. Its totient is φ = 6368705780976.

The previous prime is 20211221210021. The next prime is 20211221210027. The reversal of 20211221210022 is 22001212211202.

It is a happy number.

20211221210022 is a `hidden beast` number, since 2 + 0 + 211 + 221 + 210 + 0 + 22 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 20211221209977 and 20211221210004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20211221210021) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 63661458 + ... + 63978149.

It is an arithmetic number, because the mean of its divisors is an integer number (962402644320).

Almost surely, 2^{20211221210022} is an apocalyptic number.

20211221210022 is an abundant number, since it is smaller than the sum of its proper divisors (25984105717338).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20211221210022 is a wasteful number, since it uses less digits than its factorization.

20211221210022 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127640097 (or 127640094 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 20211221210022 its reverse (22001212211202), we get a palindrome (42212433421224).

The spelling of 20211221210022 in words is "twenty trillion, two hundred eleven billion, two hundred twenty-one million, two hundred ten thousand, twenty-two".