221102121221 has 16 divisors (see below), whose sum is σ = 229493772288. Its totient is φ = 212790144000.

The previous prime is 221102121187. The next prime is 221102121241. The reversal of 221102121221 is 122121201122.

221102121221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221102121221 is a prime.

It is a super-2 number, since 2×221102121221² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221102121221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221102121241) 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 15 ways as a sum of consecutive naturals, for example, 16805996 + ... + 16819146.

It is an arithmetic number, because the mean of its divisors is an integer number (14343360768).

Almost surely, 2^221102121221 is an apocalyptic number.

It is an amenable number.

221102121221 is a deficient number, since it is larger than the sum of its proper divisors (8391651067).

221102121221 is a wasteful number, since it uses less digits than its factorization.

221102121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16132.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 221102121221 its reverse (122121201122), we get a palindrome (343223322343).

The spelling of 221102121221 in words is "two hundred twenty-one billion, one hundred two million, one hundred twenty-one thousand, two hundred twenty-one".