21044273 has 4 divisors (see below), whose sum is σ = 21055488. Its totient is φ = 21033060.

The previous prime is 21044269. The next prime is 21044279. The reversal of 21044273 is 37244012.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21044273 - 2² = 21044269 is a prime.

It is a super-2 number, since 2×21044273² = 885722852197058, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21044279) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2033 + ... + 6798.

It is an arithmetic number, because the mean of its divisors is an integer number (5263872).

Almost surely, 2^21044273 is an apocalyptic number.

It is an amenable number.

21044273 is a deficient number, since it is larger than the sum of its proper divisors (11215).

21044273 is an equidigital number, since it uses as much as digits as its factorization.

21044273 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11214.

The product of its (nonzero) digits is 1344, while the sum is 23.

The square root of 21044273 is about 4587.4037319599. The cubic root of 21044273 is about 276.0861638491.

Adding to 21044273 its reverse (37244012), we get a palindrome (58288285).

The spelling of 21044273 in words is "twenty-one million, forty-four thousand, two hundred seventy-three".