21220121220111 has 48 divisors (see below), whose sum is σ = 35199827994240. Its totient is φ = 12183047472960.

The previous prime is 21220121220107. The next prime is 21220121220113. The reversal of 21220121220111 is 11102212102212.

21220121220111 is a `hidden beast` number, since 21 + 220 + 1 + 212 + 201 + 11 = 666.

It is not a de Polignac number, because 21220121220111 - 2² = 21220121220107 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220121220113) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 30784021 + ... + 31465793.

It is an arithmetic number, because the mean of its divisors is an integer number (733329749880).

Almost surely, 2^{21220121220111} is an apocalyptic number.

21220121220111 is a deficient number, since it is larger than the sum of its proper divisors (13979706774129).

21220121220111 is a wasteful number, since it uses less digits than its factorization.

21220121220111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 698356 (or 698353 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21220121220111 its reverse (11102212102212), we get a palindrome (32322333322323).

The spelling of 21220121220111 in words is "twenty-one trillion, two hundred twenty billion, one hundred twenty-one million, two hundred twenty thousand, one hundred eleven".