21011120112221 has 16 divisors (see below), whose sum is σ = 22382283504000. Its totient is φ = 19667173413888.

The previous prime is 21011120112197. The next prime is 21011120112239. The reversal of 21011120112221 is 12221102111012.

It is a cyclic number.

It is not a de Polignac number, because 21011120112221 - 2¹⁴ = 21011120095837 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21011120112221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011120112251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8412320 + ... + 10620233.

It is an arithmetic number, because the mean of its divisors is an integer number (1398892719000).

Almost surely, 2^{21011120112221} is an apocalyptic number.

It is an amenable number.

21011120112221 is a deficient number, since it is larger than the sum of its proper divisors (1371163391779).

21011120112221 is a wasteful number, since it uses less digits than its factorization.

21011120112221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19033268.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21011120112221 its reverse (12221102111012), we get a palindrome (33232222223233).

The spelling of 21011120112221 in words is "twenty-one trillion, eleven billion, one hundred twenty million, one hundred twelve thousand, two hundred twenty-one".