21544132544 has 28 divisors (see below), whose sum is σ = 46638152088. Its totient is φ = 9792787200.

The previous prime is 21544132529. The next prime is 21544132549. The reversal of 21544132544 is 44523144512.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21544132549) 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 in 3 ways as a sum of consecutive naturals, for example, 15300527 + ... + 15301934.

Almost surely, 2^21544132544 is an apocalyptic number.

It is an amenable number.

21544132544 is an abundant number, since it is smaller than the sum of its proper divisors (25094019544).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21544132544 is a wasteful number, since it uses less digits than its factorization.

21544132544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30602484 (or 30602474 counting only the distinct ones).

The product of its digits is 76800, while the sum is 35.

The spelling of 21544132544 in words is "twenty-one billion, five hundred forty-four million, one hundred thirty-two thousand, five hundred forty-four".