221221022100221 has 128 divisors (see below), whose sum is σ = 281702966856192. Its totient is φ = 170634608640000.

The previous prime is 221221022100167. The next prime is 221221022100229. The reversal of 221221022100221 is 122001220122122.

It is not a de Polignac number, because 221221022100221 - 2⁴⁶ = 150852277922557 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221221022100193 and 221221022100202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221221022100229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 9749273486 + ... + 9749296176.

It is an arithmetic number, because the mean of its divisors is an integer number (2200804428564).

Almost surely, 2^{221221022100221} is an apocalyptic number.

It is an amenable number.

221221022100221 is a deficient number, since it is larger than the sum of its proper divisors (60481944755971).

221221022100221 is a wasteful number, since it uses less digits than its factorization.

221221022100221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23343.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 221221022100221 its reverse (122001220122122), we get a palindrome (343222242222343).

The spelling of 221221022100221 in words is "two hundred twenty-one trillion, two hundred twenty-one billion, twenty-two million, one hundred thousand, two hundred twenty-one".