111222021221 has 4 divisors (see below), whose sum is σ = 111558039744. Its totient is φ = 110886002700.

The previous prime is 111222021199. The next prime is 111222021223. The reversal of 111222021221 is 122120222111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111222021221 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 111222021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111222021223) 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, 168008765 + ... + 168009426.

It is an arithmetic number, because the mean of its divisors is an integer number (27889509936).

Almost surely, 2^111222021221 is an apocalyptic number.

It is an amenable number.

111222021221 is a deficient number, since it is larger than the sum of its proper divisors (336018523).

111222021221 is an equidigital number, since it uses as much as digits as its factorization.

111222021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 336018522.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 111222021221 its reverse (122120222111), we get a palindrome (233342243332).

The spelling of 111222021221 in words is "one hundred eleven billion, two hundred twenty-two million, twenty-one thousand, two hundred twenty-one".