21449039 has 4 divisors (see below), whose sum is σ = 21513024. Its totient is φ = 21385056.

The previous prime is 21448961. The next prime is 21449083. The reversal of 21449039 is 93094412.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21449039 - 2¹⁶ = 21383503 is a prime.

It is a super-2 number, since 2×21449039² = 920122548047042, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21448996 and 21449014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21449539) 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, 31487 + ... + 32160.

It is an arithmetic number, because the mean of its divisors is an integer number (5378256).

Almost surely, 2^21449039 is an apocalyptic number.

21449039 is a deficient number, since it is larger than the sum of its proper divisors (63985).

21449039 is an equidigital number, since it uses as much as digits as its factorization.

21449039 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63984.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 21449039 is about 4631.3107215992. The cubic root of 21449039 is about 277.8450173877.

The spelling of 21449039 in words is "twenty-one million, four hundred forty-nine thousand, thirty-nine".