21220011221111 has 16 divisors (see below), whose sum is σ = 22567623452640. Its totient is φ = 19883450557440.

The previous prime is 21220011221081. The next prime is 21220011221173. The reversal of 21220011221111 is 11112211002212.

It is a cyclic number.

It is not a de Polignac number, because 21220011221111 - 2¹⁰ = 21220011220087 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a self number, because there is not a number n which added to its sum of digits gives 21220011221111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220011223111) 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 15 ways as a sum of consecutive naturals, for example, 74139500 + ... + 74425166.

It is an arithmetic number, because the mean of its divisors is an integer number (1410476465790).

Almost surely, 2^{21220011221111} is an apocalyptic number.

21220011221111 is a deficient number, since it is larger than the sum of its proper divisors (1347612231529).

21220011221111 is a wasteful number, since it uses less digits than its factorization.

21220011221111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304994.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21220011221111 its reverse (11112211002212), we get a palindrome (32332222223323).

The spelling of 21220011221111 in words is "twenty-one trillion, two hundred twenty billion, eleven million, two hundred twenty-one thousand, one hundred eleven".