21331002112221 has 16 divisors (see below), whose sum is σ = 28590682917888. Its totient is φ = 14145996979200.

The previous prime is 21331002112207. The next prime is 21331002112339. The reversal of 21331002112221 is 12221120013312.

It is not a de Polignac number, because 21331002112221 - 2⁹ = 21331002111709 is a prime.

It is a super-2 number, since 2×21331002112221² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21331002112201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42667461 + ... + 43164501.

It is an arithmetic number, because the mean of its divisors is an integer number (1786917682368).

Almost surely, 2^{21331002112221} is an apocalyptic number.

It is an amenable number.

21331002112221 is a deficient number, since it is larger than the sum of its proper divisors (7259680805667).

21331002112221 is a wasteful number, since it uses less digits than its factorization.

21331002112221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 572132.

The product of its (nonzero) digits is 288, while the sum is 21.

Adding to 21331002112221 its reverse (12221120013312), we get a palindrome (33552122125533).

The spelling of 21331002112221 in words is "twenty-one trillion, three hundred thirty-one billion, two million, one hundred twelve thousand, two hundred twenty-one".