21330330 has 32 divisors (see below), whose sum is σ = 58506624. Its totient is φ = 4875456.

The previous prime is 21330313. The next prime is 21330347. The reversal of 21330330 is 3303312.

It is an interprime number because it is at equal distance from previous prime (21330313) and next prime (21330347).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a plaindrome in base 16.

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, 50577 + ... + 50996.

It is an arithmetic number, because the mean of its divisors is an integer number (1828332).

Almost surely, 2^21330330 is an apocalyptic number.

21330330 is an abundant number, since it is smaller than the sum of its proper divisors (37176294).

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

21330330 is a wasteful number, since it uses less digits than its factorization.

21330330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101590.

The product of its (nonzero) digits is 162, while the sum is 15.

The square root of 21330330 is about 4618.4770217032. The cubic root of 21330330 is about 277.3314941605.

Adding to 21330330 its reverse (3303312), we get a palindrome (24633642).

The spelling of 21330330 in words is "twenty-one million, three hundred thirty thousand, three hundred thirty".