21138588512 has 24 divisors (see below), whose sum is σ = 42959068992. Its totient is φ = 10228348800.

The previous prime is 21138588461. The next prime is 21138588551. The reversal of 21138588512 is 21588583112.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10653539 + ... + 10655522.

It is an arithmetic number, because the mean of its divisors is an integer number (1789961208).

Almost surely, 2^21138588512 is an apocalyptic number.

It is an amenable number.

21138588512 is an abundant number, since it is smaller than the sum of its proper divisors (21820480480).

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

21138588512 is a wasteful number, since it uses less digits than its factorization.

21138588512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21309102 (or 21309094 counting only the distinct ones).

The product of its digits is 153600, while the sum is 44.

The spelling of 21138588512 in words is "twenty-one billion, one hundred thirty-eight million, five hundred eighty-eight thousand, five hundred twelve".