21532409712 has 240 divisors, whose sum is σ = 71628748800. Its totient is φ = 6140759040.

The previous prime is 21532409711. The next prime is 21532409747. The reversal of 21532409712 is 21790423512.

21532409712 is a `hidden beast` number, since 21 + 532 + 4 + 0 + 97 + 12 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21532409711) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 1365489 + ... + 1381167.

It is an arithmetic number, because the mean of its divisors is an integer number (298453120).

Almost surely, 2^21532409712 is an apocalyptic number.

21532409712 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21532409712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35814374400).

21532409712 is an abundant number, since it is smaller than the sum of its proper divisors (50096339088).

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

21532409712 is a wasteful number, since it uses less digits than its factorization.

21532409712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15741 (or 15712 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The spelling of 21532409712 in words is "twenty-one billion, five hundred thirty-two million, four hundred nine thousand, seven hundred twelve".