21532643947584 has 2079 divisors, whose sum is σ = 84679994420343. Its totient is φ = 5412478579200.

The previous prime is 21532643947531. The next prime is 21532643947601. The reversal of 21532643947584 is 48574934623512.

The square root of 21532643947584 is 4640328.

It is a perfect power (a square), and thus also a powerful number.

21532643947584 is a `hidden beast` number, since 2 + 1 + 5 + 3 + 2 + 6 + 4 + 3 + 9 + 47 + 584 = 666.

It is a tau number, because it is divible by the number of its divisors (2079).

It is a Harshad number since it is a multiple of its sum of digits (63).

Its product of digits (174182400) is a multiple of the sum of its prime divisors (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 296 ways as a sum of consecutive naturals, for example, 694601417649 + ... + 694601417679.

Almost surely, 2^{21532643947584} is an apocalyptic number.

21532643947584 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

21532643947584 is the 4640328-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21532643947584

21532643947584 is an abundant number, since it is smaller than the sum of its proper divisors (63147350472759).

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

21532643947584 is an frugal number, since it uses more digits than its factorization.

21532643947584 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140 (or 54 counting only the distinct ones).

The product of its digits is 174182400, while the sum is 63.

The spelling of 21532643947584 in words is "twenty-one trillion, five hundred thirty-two billion, six hundred forty-three million, nine hundred forty-seven thousand, five hundred eighty-four".