21567212384 has 96 divisors (see below), whose sum is σ = 46306663200. Its totient is φ = 9846448128.

The previous prime is 21567212383. The next prime is 21567212419. The reversal of 21567212384 is 48321276512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21567212383) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7989467 + ... + 7992165.

It is an arithmetic number, because the mean of its divisors is an integer number (482361075).

Almost surely, 2^21567212384 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21567212384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23153331600).

21567212384 is an abundant number, since it is smaller than the sum of its proper divisors (24739450816).

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

21567212384 is a wasteful number, since it uses less digits than its factorization.

21567212384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3160 (or 3152 counting only the distinct ones).

The product of its digits is 161280, while the sum is 41.

Adding to 21567212384 its reverse (48321276512), we get a palindrome (69888488896).

The spelling of 21567212384 in words is "twenty-one billion, five hundred sixty-seven million, two hundred twelve thousand, three hundred eighty-four".