21539523484 has 12 divisors (see below), whose sum is σ = 38171308000. Its totient is φ = 10633435488.

The previous prime is 21539523479. The next prime is 21539523517. The reversal of 21539523484 is 48432593512.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34081209 + ... + 34081840.

Almost surely, 2^21539523484 is an apocalyptic number.

It is an amenable number.

21539523484 is a deficient number, since it is larger than the sum of its proper divisors (16631784516).

21539523484 is a wasteful number, since it uses less digits than its factorization.

21539523484 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68163132 (or 68163130 counting only the distinct ones).

The product of its digits is 1036800, while the sum is 46.

The spelling of 21539523484 in words is "twenty-one billion, five hundred thirty-nine million, five hundred twenty-three thousand, four hundred eighty-four".