21105131103 has 12 divisors (see below), whose sum is σ = 34840216528. Its totient is φ = 12060074880.

The previous prime is 21105131059. The next prime is 21105131137. The reversal of 21105131103 is 30113150112.

It is not a de Polignac number, because 21105131103 - 2⁸ = 21105130847 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21105131183) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 167500978 + ... + 167501103.

Almost surely, 2^21105131103 is an apocalyptic number.

21105131103 is a deficient number, since it is larger than the sum of its proper divisors (13735085425).

21105131103 is a wasteful number, since it uses less digits than its factorization.

21105131103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 335002094 (or 335002091 counting only the distinct ones).

The product of its (nonzero) digits is 90, while the sum is 18.

Adding to 21105131103 its reverse (30113150112), we get a palindrome (51218281215).

The spelling of 21105131103 in words is "twenty-one billion, one hundred five million, one hundred thirty-one thousand, one hundred three".