20001221000022 has 64 divisors (see below), whose sum is σ = 42523420927680. Its totient is φ = 6250023223296.

The previous prime is 20001221000011. The next prime is 20001221000023. The reversal of 20001221000022 is 22000012210002.

It is a junction number, because it is equal to n+sod(n) for n = 20001220999971 and 20001221000007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20001221000023) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 674130604 + ... + 674160272.

It is an arithmetic number, because the mean of its divisors is an integer number (664428451995).

Almost surely, 2^{20001221000022} is an apocalyptic number.

20001221000022 is an abundant number, since it is smaller than the sum of its proper divisors (22522199927658).

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

20001221000022 is a wasteful number, since it uses less digits than its factorization.

20001221000022 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55665.

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 20001221000022 its reverse (22000012210002), we get a palindrome (42001233210024).

The spelling of 20001221000022 in words is "twenty trillion, one billion, two hundred twenty-one million, twenty-two", and thus it is an aban number.