21122102222221 has 64 divisors (see below), whose sum is σ = 28574331641856. Its totient is φ = 15078189657600.

The previous prime is 21122102222201. The next prime is 21122102222237. The reversal of 21122102222221 is 12222220122112.

It is a cyclic number.

It is not a de Polignac number, because 21122102222221 - 2³⁹ = 20572346408333 is a prime.

It is a super-2 number, since 2×21122102222221² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21122102222192 and 21122102222201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122102222201) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 71455036 + ... + 71750026.

It is an arithmetic number, because the mean of its divisors is an integer number (446473931904).

Almost surely, 2^{21122102222221} is an apocalyptic number.

It is an amenable number.

21122102222221 is a deficient number, since it is larger than the sum of its proper divisors (7452229419635).

21122102222221 is a wasteful number, since it uses less digits than its factorization.

21122102222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295562.

The product of its (nonzero) digits is 512, while the sum is 22.

Adding to 21122102222221 its reverse (12222220122112), we get a palindrome (33344322344333).

The spelling of 21122102222221 in words is "twenty-one trillion, one hundred twenty-two billion, one hundred two million, two hundred twenty-two thousand, two hundred twenty-one".