21321020032 has 64 divisors (see below), whose sum is σ = 45846297000. Its totient is φ = 9818210304.

The previous prime is 21321020029. The next prime is 21321020051. The reversal of 21321020032 is 23002012312.

It can be written as a sum of positive squares in 4 ways, for example, as 11548511296 + 9772508736 = 107464^2 + 98856^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 21321019988 and 21321020015.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 732868 + ... + 761404.

Almost surely, 2^21321020032 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 21321020032, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22923148500).

21321020032 is an abundant number, since it is smaller than the sum of its proper divisors (24525276968).

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

21321020032 is a wasteful number, since it uses less digits than its factorization.

21321020032 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29013 (or 29001 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

Adding to 21321020032 its reverse (23002012312), we get a palindrome (44323032344).

The spelling of 21321020032 in words is "twenty-one billion, three hundred twenty-one million, twenty thousand, thirty-two".