21066133 has 4 divisors (see below), whose sum is σ = 22981248. Its totient is φ = 19151020.

The previous prime is 21066113. The next prime is 21066181. The reversal of 21066133 is 33166012.

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 21066133 - 2⁹ = 21065621 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21066113) 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 3 ways as a sum of consecutive naturals, for example, 957541 + ... + 957562.

It is an arithmetic number, because the mean of its divisors is an integer number (5745312).

Almost surely, 2^21066133 is an apocalyptic number.

It is an amenable number.

21066133 is a deficient number, since it is larger than the sum of its proper divisors (1915115).

21066133 is a wasteful number, since it uses less digits than its factorization.

21066133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1915114.

The product of its (nonzero) digits is 648, while the sum is 22.

The square root of 21066133 is about 4589.7857248460. The cubic root of 21066133 is about 276.1817267452.

The spelling of 21066133 in words is "twenty-one million, sixty-six thousand, one hundred thirty-three".