21211010011221 has 32 divisors (see below), whose sum is σ = 29797464576000. Its totient is φ = 13383999940608.

The previous prime is 21211010011151. The next prime is 21211010011237. The reversal of 21211010011221 is 12211001011212.

It is a happy number.

It is not a de Polignac number, because 21211010011221 - 2¹¹ = 21211010009173 is a prime.

It is a super-2 number, since 2×21211010011221² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21211010011221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211010011291) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 403385910 + ... + 403438488.

It is an arithmetic number, because the mean of its divisors is an integer number (931170768000).

Almost surely, 2^{21211010011221} is an apocalyptic number.

It is an amenable number.

21211010011221 is a deficient number, since it is larger than the sum of its proper divisors (8586454564779).

21211010011221 is a wasteful number, since it uses less digits than its factorization.

21211010011221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59033.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21211010011221 its reverse (12211001011212), we get a palindrome (33422011022433).

Subtracting from 21211010011221 its reverse (12211001011212), we obtain a palindrome (9000009000009).

The spelling of 21211010011221 in words is "twenty-one trillion, two hundred eleven billion, ten million, eleven thousand, two hundred twenty-one".