21387999532032 has 528 divisors, whose sum is σ = 73719584389440. Its totient is φ = 6107763916800.

The previous prime is 21387999532019. The next prime is 21387999532073. The reversal of 21387999532032 is 23023599978312.

21387999532032 is a `hidden beast` number, since 2 + 1 + 3 + 8 + 7 + 9 + 99 + 532 + 0 + 3 + 2 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4837817182 + ... + 4837821602.

It is an arithmetic number, because the mean of its divisors is an integer number (139620424980).

Almost surely, 2^{21387999532032} 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 21387999532032, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36859792194720).

21387999532032 is an abundant number, since it is smaller than the sum of its proper divisors (52331584857408).

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

21387999532032 is a wasteful number, since it uses less digits than its factorization.

21387999532032 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8035 (or 8004 counting only the distinct ones).

The product of its (nonzero) digits is 44089920, while the sum is 63.

The spelling of 21387999532032 in words is "twenty-one trillion, three hundred eighty-seven billion, nine hundred ninety-nine million, five hundred thirty-two thousand, thirty-two".