21440041 has 4 divisors (see below), whose sum is σ = 24502912. Its totient is φ = 18377172.

The previous prime is 21440039. The next prime is 21440051. The reversal of 21440041 is 14004412.

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 21440041 - 2¹ = 21440039 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21439997 and 21440024.

It is not an unprimeable number, because it can be changed into a prime (21440051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1531425 + ... + 1531438.

It is an arithmetic number, because the mean of its divisors is an integer number (6125728).

Almost surely, 2^21440041 is an apocalyptic number.

It is an amenable number.

21440041 is a deficient number, since it is larger than the sum of its proper divisors (3062871).

21440041 is an equidigital number, since it uses as much as digits as its factorization.

21440041 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3062870.

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 21440041 is about 4630.3391884397. The cubic root of 21440041 is about 277.8061594052.

Adding to 21440041 its reverse (14004412), we get a palindrome (35444453).

The spelling of 21440041 in words is "twenty-one million, four hundred forty thousand, forty-one".