20111221211101 has 4 divisors (see below), whose sum is σ = 20115309693600. Its totient is φ = 20107132728604.

The previous prime is 20111221211071. The next prime is 20111221211141. The reversal of 20111221211101 is 10111212211102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20111221211101 - 2⁵ = 20111221211069 is a prime.

It is a super-2 number, since 2×20111221211101² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20111221211141) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2044233871 + ... + 2044243708.

It is an arithmetic number, because the mean of its divisors is an integer number (5028827423400).

Almost surely, 2^{20111221211101} is an apocalyptic number.

It is an amenable number.

20111221211101 is a deficient number, since it is larger than the sum of its proper divisors (4088482499).

20111221211101 is an equidigital number, since it uses as much as digits as its factorization.

20111221211101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4088482498.

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

Adding to 20111221211101 its reverse (10111212211102), we get a palindrome (30222433422203).

It can be divided in two parts, 2011122 and 1211101, that added together give a palindrome (3222223).

The spelling of 20111221211101 in words is "twenty trillion, one hundred eleven billion, two hundred twenty-one million, two hundred eleven thousand, one hundred one".