21020320032 has 24 divisors (see below), whose sum is σ = 55178340336. Its totient is φ = 7006773312.

The previous prime is 21020319959. The next prime is 21020320033. The reversal of 21020320032 is 23002302012.

It is a tau number, because it is divible by the number of its divisors (24).

It is a junction number, because it is equal to n+sod(n) for n = 21020319993 and 21020320020.

It is not an unprimeable number, because it can be changed into a prime (21020320033) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 109480738 + ... + 109480929.

It is an arithmetic number, because the mean of its divisors is an integer number (2299097514).

Almost surely, 2^21020320032 is an apocalyptic number.

It is an amenable number.

21020320032 is an abundant number, since it is smaller than the sum of its proper divisors (34158020304).

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

21020320032 is a wasteful number, since it uses less digits than its factorization.

21020320032 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218961680 (or 218961672 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

Adding to 21020320032 its reverse (23002302012), we get a palindrome (44022622044).

The spelling of 21020320032 in words is "twenty-one billion, twenty million, three hundred twenty thousand, thirty-two".