21330080 has 48 divisors (see below), whose sum is σ = 52141320. Its totient is φ = 8236032.

The previous prime is 21330073. The next prime is 21330083. The reversal of 21330080 is 8003312.

It can be written as a sum of positive squares in 4 ways, for example, as 12306064 + 9024016 = 3508^2 + 3004^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21330083) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2342 + ... + 6938.

Almost surely, 2^21330080 is an apocalyptic number.

21330080 is a gapful number since it is divisible by the number (20) 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 21330080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26070660).

21330080 is an abundant number, since it is smaller than the sum of its proper divisors (30811240).

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

21330080 is a wasteful number, since it uses less digits than its factorization.

21330080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4641 (or 4633 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 21330080 is about 4618.4499564248. The cubic root of 21330080 is about 277.3304106776.

Adding to 21330080 its reverse (8003312), we get a palindrome (29333392).

The spelling of 21330080 in words is "twenty-one million, three hundred thirty thousand, eighty".