21744069 has 8 divisors (see below), whose sum is σ = 29017920. Its totient is φ = 14483136.

The previous prime is 21744043. The next prime is 21744089. The reversal of 21744069 is 96044712.

It is a happy number.

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

It is not a de Polignac number, because 21744069 - 2¹⁵ = 21711301 is a prime.

It is a super-2 number, since 2×21744069² = 945609073353522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21744089) 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 7 ways as a sum of consecutive naturals, for example, 1837 + ... + 6845.

It is an arithmetic number, because the mean of its divisors is an integer number (3627240).

Almost surely, 2^21744069 is an apocalyptic number.

It is an amenable number.

21744069 is a deficient number, since it is larger than the sum of its proper divisors (7273851).

21744069 is a wasteful number, since it uses less digits than its factorization.

21744069 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6459.

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 21744069 is about 4663.0536132453. The cubic root of 21744069 is about 279.1131335484.

The spelling of 21744069 in words is "twenty-one million, seven hundred forty-four thousand, sixty-nine".