21221020000111 has 4 divisors (see below), whose sum is σ = 21439793402272. Its totient is φ = 21002246597952.

The previous prime is 21221020000069. The next prime is 21221020000157. The reversal of 21221020000111 is 11100002012212.

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

It is a cyclic number.

It is not a de Polignac number, because 21221020000111 - 2¹⁹ = 21221019475823 is a prime.

It is a super-2 number, since 2×21221020000111² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21221020000091 and 21221020000100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221020000171) 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, 109386700935 + ... + 109386701128.

It is an arithmetic number, because the mean of its divisors is an integer number (5359948350568).

Almost surely, 2^{21221020000111} is an apocalyptic number.

21221020000111 is a deficient number, since it is larger than the sum of its proper divisors (218773402161).

21221020000111 is an equidigital number, since it uses as much as digits as its factorization.

21221020000111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 218773402160.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21221020000111 its reverse (11100002012212), we get a palindrome (32321022012323).

The spelling of 21221020000111 in words is "twenty-one trillion, two hundred twenty-one billion, twenty million, one hundred eleven", and thus it is an aban number.