21220311109 has 2 divisors, whose sum is σ = 21220311110. Its totient is φ = 21220311108.

The previous prime is 21220311061. The next prime is 21220311127. The reversal of 21220311109 is 90111302212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11069144100 + 10151167009 = 105210^2 + 100753^2 .

It is a cyclic number.

It is not a de Polignac number, because 21220311109 - 2¹⁵ = 21220278341 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21220311109.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21220311209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610155554 + 10610155555.

It is an arithmetic number, because the mean of its divisors is an integer number (10610155555).

Almost surely, 2^21220311109 is an apocalyptic number.

It is an amenable number.

21220311109 is a deficient number, since it is larger than the sum of its proper divisors (1).

21220311109 is an equidigital number, since it uses as much as digits as its factorization.

21220311109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 22.

The spelling of 21220311109 in words is "twenty-one billion, two hundred twenty million, three hundred eleven thousand, one hundred nine".