221121101201221 has 16 divisors (see below), whose sum is σ = 238451179302000. Its totient is φ = 203837023369728.

The previous prime is 221121101201213. The next prime is 221121101201279. The reversal of 221121101201221 is 122102101121122.

It is a happy number.

221121101201221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 541127956996 + 220579973244225 = 735614^2 + 14851935^2 .

It is a cyclic number.

It is not a de Polignac number, because 221121101201221 - 2³ = 221121101201213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221121101201321) 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, 26302105 + ... + 33675553.

It is an arithmetic number, because the mean of its divisors is an integer number (14903198706375).

Almost surely, 2^{221121101201221} is an apocalyptic number.

It is an amenable number.

221121101201221 is a deficient number, since it is larger than the sum of its proper divisors (17330078100779).

221121101201221 is a wasteful number, since it uses less digits than its factorization.

221121101201221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7376568.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 221121101201221 its reverse (122102101121122), we get a palindrome (343223202322343).

The spelling of 221121101201221 in words is "two hundred twenty-one trillion, one hundred twenty-one billion, one hundred one million, two hundred one thousand, two hundred twenty-one".