121111212110221 has 4 divisors (see below), whose sum is σ = 121780334829244. Its totient is φ = 120442089391200.

The previous prime is 121111212110219. The next prime is 121111212110227. The reversal of 121111212110221 is 122011212111121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11583056685321 + 109528155424900 = 3403389^2 + 10465570^2 .

It is a cyclic number.

It is not a de Polignac number, because 121111212110221 - 2¹ = 121111212110219 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 (121111212110227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 334561359240 + ... + 334561359601.

It is an arithmetic number, because the mean of its divisors is an integer number (30445083707311).

Almost surely, 2^{121111212110221} is an apocalyptic number.

It is an amenable number.

121111212110221 is a deficient number, since it is larger than the sum of its proper divisors (669122719023).

121111212110221 is an equidigital number, since it uses as much as digits as its factorization.

121111212110221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 669122719022.

The product of its (nonzero) digits is 32, while the sum is 19.

Adding to 121111212110221 its reverse (122011212111121), we get a palindrome (243122424221342).

The spelling of 121111212110221 in words is "one hundred twenty-one trillion, one hundred eleven billion, two hundred twelve million, one hundred ten thousand, two hundred twenty-one".