1111111210221 has 16 divisors (see below), whose sum is σ = 1509556512960. Its totient is φ = 726705624320.

The previous prime is 1111111210213. The next prime is 1111111210229. The reversal of 1111111210221 is 1220121111111.

It is an interprime number because it is at equal distance from previous prime (1111111210213) and next prime (1111111210229).

It is a cyclic number.

It is not a de Polignac number, because 1111111210221 - 2³ = 1111111210213 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1111111210221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1111111210229) 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, 1728085 + ... + 2282213.

It is an arithmetic number, because the mean of its divisors is an integer number (94347282060).

Almost surely, 2^{1111111210221} is an apocalyptic number.

It is an amenable number.

1111111210221 is a deficient number, since it is larger than the sum of its proper divisors (398445302739).

1111111210221 is a wasteful number, since it uses less digits than its factorization.

1111111210221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 566796.

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 1111111210221 its reverse (1220121111111), we get a palindrome (2331232321332).

The spelling of 1111111210221 in words is "one trillion, one hundred eleven billion, one hundred eleven million, two hundred ten thousand, two hundred twenty-one".