21111222021201 has 24 divisors (see below), whose sum is σ = 32869614796200. Its totient is φ = 12979678392576.

The previous prime is 21111222021191. The next prime is 21111222021203. The reversal of 21111222021201 is 10212022211112.

21111222021201 is a `hidden beast` number, since 211 + 1 + 12 + 220 + 21 + 201 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1843555666176 + 19267666355025 = 1357776^2 + 4389495^2 .

It is not a de Polignac number, because 21111222021201 - 2⁹ = 21111222020689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21111222021203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 82113126 + ... + 82369823.

It is an arithmetic number, because the mean of its divisors is an integer number (1369567283175).

Almost surely, 2^{21111222021201} is an apocalyptic number.

It is an amenable number.

21111222021201 is a deficient number, since it is larger than the sum of its proper divisors (11758392774999).

21111222021201 is a wasteful number, since it uses less digits than its factorization.

21111222021201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164484065 (or 164484062 counting only the distinct ones).

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

Adding to 21111222021201 its reverse (10212022211112), we get a palindrome (31323244232313).

The spelling of 21111222021201 in words is "twenty-one trillion, one hundred eleven billion, two hundred twenty-two million, twenty-one thousand, two hundred one".