21133133 has 4 divisors (see below), whose sum is σ = 24152160. Its totient is φ = 18114108.

The previous prime is 21133121. The next prime is 21133153. The reversal of 21133133 is 33133112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21133133 - 2⁸ = 21132877 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 (21133153) 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, 1509503 + ... + 1509516.

It is an arithmetic number, because the mean of its divisors is an integer number (6038040).

Almost surely, 2^21133133 is an apocalyptic number.

It is an amenable number.

21133133 is a deficient number, since it is larger than the sum of its proper divisors (3019027).

21133133 is an equidigital number, since it uses as much as digits as its factorization.

21133133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3019026.

The product of its digits is 162, while the sum is 17.

The square root of 21133133 is about 4597.0787463345. The cubic root of 21133133 is about 276.4742118921.

Adding to 21133133 its reverse (33133112), we get a palindrome (54266245).

The spelling of 21133133 in words is "twenty-one million, one hundred thirty-three thousand, one hundred thirty-three".