221121021111 has 4 divisors (see below), whose sum is σ = 294828028152. Its totient is φ = 147414014072.

The previous prime is 221121021083. The next prime is 221121021131. The reversal of 221121021111 is 111120121122.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 221121021111 - 2²⁷ = 220986803383 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221121021131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36853503516 + ... + 36853503521.

It is an arithmetic number, because the mean of its divisors is an integer number (73707007038).

Almost surely, 2^221121021111 is an apocalyptic number.

221121021111 is a deficient number, since it is larger than the sum of its proper divisors (73707007041).

221121021111 is an equidigital number, since it uses as much as digits as its factorization.

221121021111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73707007040.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 221121021111 its reverse (111120121122), we get a palindrome (332241142233).

The spelling of 221121021111 in words is "two hundred twenty-one billion, one hundred twenty-one million, twenty-one thousand, one hundred eleven".