21011120221221 has 40 divisors (see below), whose sum is σ = 33801851714400. Its totient is φ = 12929734068768.

The previous prime is 21011120221213. The next prime is 21011120221279. The reversal of 21011120221221 is 12212202111012.

21011120221221 is a `hidden beast` number, since 2 + 101 + 1 + 120 + 221 + 221 = 666.

It is not a de Polignac number, because 21011120221221 - 2³ = 21011120221213 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21011120221194 and 21011120221203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011120221121) 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 39 ways as a sum of consecutive naturals, for example, 124063026 + ... + 124232268.

It is an arithmetic number, because the mean of its divisors is an integer number (845046292860).

Almost surely, 2^{21011120221221} is an apocalyptic number.

It is an amenable number.

21011120221221 is a deficient number, since it is larger than the sum of its proper divisors (12790731493179).

21011120221221 is a wasteful number, since it uses less digits than its factorization.

21011120221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287167 (or 287158 counting only the distinct ones).

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

Adding to 21011120221221 its reverse (12212202111012), we get a palindrome (33223322332233).

The spelling of 21011120221221 in words is "twenty-one trillion, eleven billion, one hundred twenty million, two hundred twenty-one thousand, two hundred twenty-one".