21330318 has 8 divisors (see below), whose sum is σ = 42660648. Its totient is φ = 7110104.

The previous prime is 21330313. The next prime is 21330347. The reversal of 21330318 is 81303312.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

21330318 is an admirable number.

It is a super-2 number, since 2×21330318² = 909964931962248, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21330294 and 21330303.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21330311) 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, 1777521 + ... + 1777532.

It is an arithmetic number, because the mean of its divisors is an integer number (5332581).

Almost surely, 2^21330318 is an apocalyptic number.

21330318 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21330318 is a wasteful number, since it uses less digits than its factorization.

21330318 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3555058.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 21330318 is about 4618.4757225734. The cubic root of 21330318 is about 277.3314421535.

The spelling of 21330318 in words is "twenty-one million, three hundred thirty thousand, three hundred eighteen".