1111221201221 has 16 divisors (see below), whose sum is σ = 1194283796544. Its totient is φ = 1030128447744.

The previous prime is 1111221201203. The next prime is 1111221201247. The reversal of 1111221201221 is 1221021221111.

It is a cyclic number.

It is not a de Polignac number, because 1111221201221 - 2¹⁰ = 1111221200197 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a self number, because there is not a number n which added to its sum of digits gives 1111221201221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1111221201271) 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, 10932791 + ... + 11033963.

It is an arithmetic number, because the mean of its divisors is an integer number (74642737284).

Almost surely, 2^{1111221201221} is an apocalyptic number.

It is an amenable number.

1111221201221 is a deficient number, since it is larger than the sum of its proper divisors (83062595323).

1111221201221 is a wasteful number, since it uses less digits than its factorization.

1111221201221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110900.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 1111221201221 its reverse (1221021221111), we get a palindrome (2332242422332).

The spelling of 1111221201221 in words is "one trillion, one hundred eleven billion, two hundred twenty-one million, two hundred one thousand, two hundred twenty-one".