21220320111 has 4 divisors (see below), whose sum is σ = 28293760152. Its totient is φ = 14146880072.

The previous prime is 21220320109. The next prime is 21220320151. The reversal of 21220320111 is 11102302212.

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 21220320111 - 2¹ = 21220320109 is a prime.

It is a super-2 number, since 2×21220320111² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220320151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3536720016 + ... + 3536720021.

It is an arithmetic number, because the mean of its divisors is an integer number (7073440038).

Almost surely, 2^21220320111 is an apocalyptic number.

21220320111 is a deficient number, since it is larger than the sum of its proper divisors (7073440041).

21220320111 is an equidigital number, since it uses as much as digits as its factorization.

21220320111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7073440040.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21220320111 its reverse (11102302212), we get a palindrome (32322622323).

The spelling of 21220320111 in words is "twenty-one billion, two hundred twenty million, three hundred twenty thousand, one hundred eleven".