1111111221021 has 4 divisors (see below), whose sum is σ = 1481481628032. Its totient is φ = 740740814012.

The previous prime is 1111111221001. The next prime is 1111111221053. The reversal of 1111111221021 is 1201221111111.

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 not a de Polignac number, because 1111111221021 - 2⁷ = 1111111220893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1111111221001) 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, 185185203501 + ... + 185185203506.

It is an arithmetic number, because the mean of its divisors is an integer number (370370407008).

Almost surely, 2^{1111111221021} is an apocalyptic number.

It is an amenable number.

1111111221021 is a deficient number, since it is larger than the sum of its proper divisors (370370407011).

1111111221021 is an equidigital number, since it uses as much as digits as its factorization.

1111111221021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 370370407010.

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

Adding to 1111111221021 its reverse (1201221111111), we get a palindrome (2312332332132).

The spelling of 1111111221021 in words is "one trillion, one hundred eleven billion, one hundred eleven million, two hundred twenty-one thousand, twenty-one".