21303233 has 8 divisors (see below), whose sum is σ = 24389568. Its totient is φ = 18227664.

The previous prime is 21303229. The next prime is 21303241. The reversal of 21303233 is 33230312.

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

It is not a de Polignac number, because 21303233 - 2² = 21303229 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21303203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2135 + ... + 6867.

It is an arithmetic number, because the mean of its divisors is an integer number (3048696).

Almost surely, 2^21303233 is an apocalyptic number.

It is an amenable number.

21303233 is a deficient number, since it is larger than the sum of its proper divisors (3086335).

21303233 is an equidigital number, since it uses as much as digits as its factorization.

21303233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5383.

The product of its (nonzero) digits is 324, while the sum is 17.

The square root of 21303233 is about 4615.5425466569. The cubic root of 21303233 is about 277.2140083096.

Adding to 21303233 its reverse (33230312), we get a palindrome (54533545).

The spelling of 21303233 in words is "twenty-one million, three hundred three thousand, two hundred thirty-three".