21330033 has 16 divisors (see below), whose sum is σ = 29030400. Its totient is φ = 13927760.

The previous prime is 21329999. The next prime is 21330047. The reversal of 21330033 is 33003312.

It is a cyclic number.

It is not a de Polignac number, because 21330033 - 2⁶ = 21329969 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21329994 and 21330021.

It is not an unprimeable number, because it can be changed into a prime (21330073) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50698 + ... + 51116.

It is an arithmetic number, because the mean of its divisors is an integer number (1814400).

Almost surely, 2^21330033 is an apocalyptic number.

It is an amenable number.

21330033 is a deficient number, since it is larger than the sum of its proper divisors (7700367).

21330033 is a wasteful number, since it uses less digits than its factorization.

21330033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 732.

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

The square root of 21330033 is about 4618.4448681347. Note that the first 3 decimals coincide. The cubic root of 21330033 is about 277.3302069819.

Adding to 21330033 its reverse (33003312), we get a palindrome (54333345).

The spelling of 21330033 in words is "twenty-one million, three hundred thirty thousand, thirty-three".