21126684481 has 16 divisors (see below), whose sum is σ = 24928703488. Its totient is φ = 17520883200.

The previous prime is 21126684457. The next prime is 21126684529. The reversal of 21126684481 is 18448662112.

It is a cyclic number.

It is not a de Polignac number, because 21126684481 - 2⁹ = 21126683969 is a prime.

It is a super-2 number, since 2×21126684481² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21126684881) 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, 2041801 + ... + 2052121.

It is an arithmetic number, because the mean of its divisors is an integer number (1558043968).

Almost surely, 2^21126684481 is an apocalyptic number.

It is an amenable number.

21126684481 is a deficient number, since it is larger than the sum of its proper divisors (3802019007).

21126684481 is a wasteful number, since it uses less digits than its factorization.

21126684481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19792.

The product of its digits is 147456, while the sum is 43.

The spelling of 21126684481 in words is "twenty-one billion, one hundred twenty-six million, six hundred eighty-four thousand, four hundred eighty-one".