21042020032 has 84 divisors (see below), whose sum is σ = 46352417328. Its totient is φ = 9469504000.

The previous prime is 21042020023. The next prime is 21042020033. The reversal of 21042020032 is 23002024012.

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 = 21042019988 and 21042020015.

It is not an unprimeable number, because it can be changed into a prime (21042020033) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 768693 + ... + 795595.

It is an arithmetic number, because the mean of its divisors is an integer number (551814492).

Almost surely, 2^21042020032 is an apocalyptic number.

21042020032 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21042020032, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23176208664).

21042020032 is an abundant number, since it is smaller than the sum of its proper divisors (25310397296).

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

21042020032 is a wasteful number, since it uses less digits than its factorization.

21042020032 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27038 (or 27017 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

Adding to 21042020032 its reverse (23002024012), we get a palindrome (44044044044).

The spelling of 21042020032 in words is "twenty-one billion, forty-two million, twenty thousand, thirty-two".