21201110110105 has 16 divisors (see below), whose sum is σ = 25707076318224. Its totient is φ = 16783772405760.

The previous prime is 21201110110073. The next prime is 21201110110121. The reversal of 21201110110105 is 50101101110212.

It can be written as a sum of positive squares in 8 ways, for example, as 433211443344 + 20767898666761 = 658188^2 + 4557181^2 .

It is not a de Polignac number, because 21201110110105 - 2⁵ = 21201110110073 is a prime.

It is a super-2 number, since 2×21201110110105² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 664495 + ... + 6545515.

It is an arithmetic number, because the mean of its divisors is an integer number (1606692269889).

Almost surely, 2^{21201110110105} is an apocalyptic number.

It is an amenable number.

21201110110105 is a deficient number, since it is larger than the sum of its proper divisors (4505966208119).

21201110110105 is an equidigital number, since it uses as much as digits as its factorization.

21201110110105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5888556.

The product of its (nonzero) digits is 20, while the sum is 16.

Adding to 21201110110105 its reverse (50101101110212), we get a palindrome (71302211220317).

The spelling of 21201110110105 in words is "twenty-one trillion, two hundred one billion, one hundred ten million, one hundred ten thousand, one hundred five".