21532251552 has 96 divisors (see below), whose sum is σ = 64638000000. Its totient is φ = 6148144128.

The previous prime is 21532251539. The next prime is 21532251569. The reversal of 21532251552 is 25515223512.

It is a tau number, because it is divible by the number of its divisors (96).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1139074 + ... + 1157822.

It is an arithmetic number, because the mean of its divisors is an integer number (673312500).

Almost surely, 2^21532251552 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 21532251552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32319000000).

21532251552 is an abundant number, since it is smaller than the sum of its proper divisors (43105748448).

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

21532251552 is a wasteful number, since it uses less digits than its factorization.

21532251552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20478 (or 20470 counting only the distinct ones).

The product of its digits is 30000, while the sum is 33.

The spelling of 21532251552 in words is "twenty-one billion, five hundred thirty-two million, two hundred fifty-one thousand, five hundred fifty-two".