21105503573 has 16 divisors (see below), whose sum is σ = 26324369280. Its totient is φ = 16438963200.

The previous prime is 21105503537. The next prime is 21105503603. The reversal of 21105503573 is 37530550112.

It is not a de Polignac number, because 21105503573 - 2¹⁰ = 21105502549 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21105502573) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 131813 + ... + 244101.

It is an arithmetic number, because the mean of its divisors is an integer number (1645273080).

Almost surely, 2^21105503573 is an apocalyptic number.

It is an amenable number.

21105503573 is a deficient number, since it is larger than the sum of its proper divisors (5218865707).

21105503573 is a wasteful number, since it uses less digits than its factorization.

21105503573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114748.

The product of its (nonzero) digits is 15750, while the sum is 32.

The spelling of 21105503573 in words is "twenty-one billion, one hundred five million, five hundred three thousand, five hundred seventy-three".