20011120121221 has 4 divisors (see below), whose sum is σ = 21188244834252. Its totient is φ = 18833995408192.

The previous prime is 20011120121207. The next prime is 20011120121227. The reversal of 20011120121221 is 12212102111002.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15330435468100 + 4680684653121 = 3915410^2 + 2163489^2 .

It is a cyclic number.

It is not a de Polignac number, because 20011120121221 - 2⁷ = 20011120121093 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20011120121195 and 20011120121204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20011120121227) 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, 588562356490 + ... + 588562356523.

It is an arithmetic number, because the mean of its divisors is an integer number (5297061208563).

Almost surely, 2^{20011120121221} is an apocalyptic number.

It is an amenable number.

20011120121221 is a deficient number, since it is larger than the sum of its proper divisors (1177124713031).

20011120121221 is a wasteful number, since it uses less digits than its factorization.

20011120121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1177124713030.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 20011120121221 its reverse (12212102111002), we get a palindrome (32223222232223).

The spelling of 20011120121221 in words is "twenty trillion, eleven billion, one hundred twenty million, one hundred twenty-one thousand, two hundred twenty-one".