21521240132 has 12 divisors (see below), whose sum is σ = 43042480320. Its totient is φ = 9223388616.

The previous prime is 21521240129. The next prime is 21521240159. The reversal of 21521240132 is 23104212512.

21521240132 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 21521240098 and 21521240107.

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, 384307832 + ... + 384307887.

It is an arithmetic number, because the mean of its divisors is an integer number (3586873360).

Almost surely, 2^21521240132 is an apocalyptic number.

It is an amenable number.

21521240132 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21521240132 is a wasteful number, since it uses less digits than its factorization.

21521240132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 768615730 (or 768615728 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

Adding to 21521240132 its reverse (23104212512), we get a palindrome (44625452644).

The spelling of 21521240132 in words is "twenty-one billion, five hundred twenty-one million, two hundred forty thousand, one hundred thirty-two".