21482209 has 4 divisors (see below), whose sum is σ = 24551104. Its totient is φ = 18413316.

The previous prime is 21482191. The next prime is 21482239. The reversal of 21482209 is 90228412.

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 21482209 - 2⁷ = 21482081 is a prime.

It is a super-2 number, since 2×21482209² = 922970607039362, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21482239) 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, 1534437 + ... + 1534450.

It is an arithmetic number, because the mean of its divisors is an integer number (6137776).

Almost surely, 2^21482209 is an apocalyptic number.

It is an amenable number.

21482209 is a deficient number, since it is larger than the sum of its proper divisors (3068895).

21482209 is an equidigital number, since it uses as much as digits as its factorization.

21482209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3068894.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 21482209 is about 4634.8903978411. The cubic root of 21482209 is about 277.9881686734.

The spelling of 21482209 in words is "twenty-one million, four hundred eighty-two thousand, two hundred nine".