21304133 has 8 divisors (see below), whose sum is σ = 22196160. Its totient is φ = 20429920.

The previous prime is 21304121. The next prime is 21304139. The reversal of 21304133 is 33140312.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21304133 - 2⁴ = 21304117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21304139) 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, 1985 + ... + 6822.

It is an arithmetic number, because the mean of its divisors is an integer number (2774520).

Almost surely, 2^21304133 is an apocalyptic number.

It is an amenable number.

21304133 is a deficient number, since it is larger than the sum of its proper divisors (892027).

21304133 is an equidigital number, since it uses as much as digits as its factorization.

21304133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8907.

The product of its (nonzero) digits is 216, while the sum is 17.

The square root of 21304133 is about 4615.6400422910. The cubic root of 21304133 is about 277.2179120848.

Adding to 21304133 its reverse (33140312), we get a palindrome (54444445).

The spelling of 21304133 in words is "twenty-one million, three hundred four thousand, one hundred thirty-three".