20001221112101 has 16 divisors (see below), whose sum is σ = 20413159619328. Its totient is φ = 19590570854400.

The previous prime is 20001221112031. The next prime is 20001221112163. The reversal of 20001221112101 is 10121112210002.

It is a cyclic number.

It is not a de Polignac number, because 20001221112101 - 2¹⁰ = 20001221111077 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 (20001221111101) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 279596000 + ... + 279667526.

It is an arithmetic number, because the mean of its divisors is an integer number (1275822476208).

Almost surely, 2^{20001221112101} is an apocalyptic number.

It is an amenable number.

20001221112101 is a deficient number, since it is larger than the sum of its proper divisors (411938507227).

20001221112101 is an equidigital number, since it uses as much as digits as its factorization.

20001221112101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80452.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 20001221112101 its reverse (10121112210002), we get a palindrome (30122333322103).

The spelling of 20001221112101 in words is "twenty trillion, one billion, two hundred twenty-one million, one hundred twelve thousand, one hundred one".