221101222101221 has 16 divisors (see below), whose sum is σ = 275699009432448. Its totient is φ = 172261452249600.

The previous prime is 221101222101209. The next prime is 221101222101269. The reversal of 221101222101221 is 122101222101122.

It is not a de Polignac number, because 221101222101221 - 2⁶ = 221101222101157 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221101222101193 and 221101222101202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221101222101271) 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, 209589800 + ... + 210642081.

It is an arithmetic number, because the mean of its divisors is an integer number (17231188089528).

Almost surely, 2^{221101222101221} is an apocalyptic number.

It is an amenable number.

221101222101221 is a deficient number, since it is larger than the sum of its proper divisors (54597787331227).

221101222101221 is a wasteful number, since it uses less digits than its factorization.

221101222101221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420238732.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 221101222101221 its reverse (122101222101122), we get a palindrome (343202444202343).

Subtracting from 221101222101221 its reverse (122101222101122), we obtain a palindrome (99000000000099).

The spelling of 221101222101221 in words is "two hundred twenty-one trillion, one hundred one billion, two hundred twenty-two million, one hundred one thousand, two hundred twenty-one".