21244033 has 16 divisors (see below), whose sum is σ = 23976000. Its totient is φ = 18703872.

The previous prime is 21244001. The next prime is 21244061. The reversal of 21244033 is 33044212.

It is a cyclic number.

It is not a de Polignac number, because 21244033 - 2⁵ = 21244001 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21244033.

It is not an unprimeable number, because it can be changed into a prime (21244063) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28378 + ... + 29116.

It is an arithmetic number, because the mean of its divisors is an integer number (1498500).

Almost surely, 2^21244033 is an apocalyptic number.

It is an amenable number.

21244033 is a deficient number, since it is larger than the sum of its proper divisors (2731967).

21244033 is a wasteful number, since it uses less digits than its factorization.

21244033 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 864.

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 21244033 is about 4609.1249711849. The cubic root of 21244033 is about 276.9569848101.

Adding to 21244033 its reverse (33044212), we get a palindrome (54288245).

The spelling of 21244033 in words is "twenty-one million, two hundred forty-four thousand, thirty-three".