21573384536 has 16 divisors (see below), whose sum is σ = 44127377640. Its totient is φ = 9806083840.

The previous prime is 21573384517. The next prime is 21573384583. The reversal of 21573384536 is 63548337512.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122575961 + ... + 122576136.

Almost surely, 2^21573384536 is an apocalyptic number.

It is an amenable number.

21573384536 is an abundant number, since it is smaller than the sum of its proper divisors (22553993104).

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

21573384536 is a wasteful number, since it uses less digits than its factorization.

21573384536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245152114 (or 245152110 counting only the distinct ones).

The product of its digits is 1814400, while the sum is 47.

The spelling of 21573384536 in words is "twenty-one billion, five hundred seventy-three million, three hundred eighty-four thousand, five hundred thirty-six".