221211120211221 has 8 divisors (see below), whose sum is σ = 337083611750464. Its totient is φ = 126406354406400.

The previous prime is 221211120211183. The next prime is 221211120211297. The reversal of 221211120211221 is 122112021112122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 221211120211221 - 2¹⁴ = 221211120194837 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 10533862867201 = 221211120211221 / (2 + 2 + 1 + 2 + 1 + 1 + 1 + 2 + 0 + 2 + 1 + 1 + 2 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221211120216221) 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 7 ways as a sum of consecutive naturals, for example, 5266931433580 + ... + 5266931433621.

It is an arithmetic number, because the mean of its divisors is an integer number (42135451468808).

Almost surely, 2^{221211120211221} is an apocalyptic number.

221211120211221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

221211120211221 is a deficient number, since it is larger than the sum of its proper divisors (115872491539243).

221211120211221 is a wasteful number, since it uses less digits than its factorization.

221211120211221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10533862867211.

The product of its (nonzero) digits is 128, while the sum is 21.

Adding to 221211120211221 its reverse (122112021112122), we get a palindrome (343323141323343).

Subtracting from 221211120211221 its reverse (122112021112122), we obtain a palindrome (99099099099099).

The spelling of 221211120211221 in words is "two hundred twenty-one trillion, two hundred eleven billion, one hundred twenty million, two hundred eleven thousand, two hundred twenty-one".