221020021111 has 4 divisors (see below), whose sum is σ = 221033487312. Its totient is φ = 221006554912.

The previous prime is 221020021097. The next prime is 221020021139. The reversal of 221020021111 is 111120020122.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 111120020122 = 2 ⋅55560010061.

It is a cyclic number.

It is not a de Polignac number, because 221020021111 - 2¹¹ = 221020019063 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221020021091 and 221020021100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221020021511) 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, 6708451 + ... + 6741316.

It is an arithmetic number, because the mean of its divisors is an integer number (55258371828).

Almost surely, 2^221020021111 is an apocalyptic number.

221020021111 is a deficient number, since it is larger than the sum of its proper divisors (13466201).

221020021111 is a wasteful number, since it uses less digits than its factorization.

221020021111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13466200.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 221020021111 its reverse (111120020122), we get a palindrome (332140041233).

The spelling of 221020021111 in words is "two hundred twenty-one billion, twenty million, twenty-one thousand, one hundred eleven".