111212221201221 has 64 divisors (see below), whose sum is σ = 175543783833600. Its totient is φ = 61285371033600.

The previous prime is 111212221201219. The next prime is 111212221201321. The reversal of 111212221201221 is 122102122212111.

It is not a de Polignac number, because 111212221201221 - 2¹ = 111212221201219 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111212221201201) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 276082485 + ... + 276485013.

It is an arithmetic number, because the mean of its divisors is an integer number (2742871622400).

Almost surely, 2^{111212221201221} is an apocalyptic number.

It is an amenable number.

111212221201221 is a deficient number, since it is larger than the sum of its proper divisors (64331562632379).

111212221201221 is a wasteful number, since it uses less digits than its factorization.

111212221201221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 404050.

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

Adding to 111212221201221 its reverse (122102122212111), we get a palindrome (233314343413332).

The spelling of 111212221201221 in words is "one hundred eleven trillion, two hundred twelve billion, two hundred twenty-one million, two hundred one thousand, two hundred twenty-one".