111211211210221 has 16 divisors (see below), whose sum is σ = 114120109509120. Its totient is φ = 108317005902000.

The previous prime is 111211211210149. The next prime is 111211211210243. The reversal of 111211211210221 is 122012112112111.

It is a cyclic number.

It is not a de Polignac number, because 111211211210221 - 2²³ = 111211202821613 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 (111211211210321) 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, 334554346 + ... + 334886596.

It is an arithmetic number, because the mean of its divisors is an integer number (7132506844320).

Almost surely, 2^{111211211210221} is an apocalyptic number.

It is an amenable number.

111211211210221 is a deficient number, since it is larger than the sum of its proper divisors (2908898298899).

111211211210221 is a wasteful number, since it uses less digits than its factorization.

111211211210221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354336.

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

Adding to 111211211210221 its reverse (122012112112111), we get a palindrome (233223323322332).

The spelling of 111211211210221 in words is "one hundred eleven trillion, two hundred eleven billion, two hundred eleven million, two hundred ten thousand, two hundred twenty-one".