20011011021221 has 32 divisors (see below), whose sum is σ = 22371290726400. Its totient is φ = 17746411737600.

The previous prime is 20011011021187. The next prime is 20011011021223. The reversal of 20011011021221 is 12212011011002.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20011011021221 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20011011021196 and 20011011021205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20011011021223) 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, 336861680 + ... + 336921078.

It is an arithmetic number, because the mean of its divisors is an integer number (699102835200).

Almost surely, 2^{20011011021221} is an apocalyptic number.

It is an amenable number.

20011011021221 is a deficient number, since it is larger than the sum of its proper divisors (2360279705179).

20011011021221 is a wasteful number, since it uses less digits than its factorization.

20011011021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64025.

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

Adding to 20011011021221 its reverse (12212011011002), we get a palindrome (32223022032223).

The spelling of 20011011021221 in words is "twenty trillion, eleven billion, eleven million, twenty-one thousand, two hundred twenty-one".