21441444 has 12 divisors (see below), whose sum is σ = 50030064. Its totient is φ = 7147144.

The previous prime is 21441421. The next prime is 21441449. The reversal of 21441444 is 44414412.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (21441449) 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, 893382 + ... + 893405.

It is an arithmetic number, because the mean of its divisors is an integer number (4169172).

Almost surely, 2^21441444 is an apocalyptic number.

It is an amenable number.

21441444 is an abundant number, since it is smaller than the sum of its proper divisors (28588620).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21441444 is a wasteful number, since it uses less digits than its factorization.

21441444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1786794 (or 1786792 counting only the distinct ones).

The product of its digits is 2048, while the sum is 24.

The square root of 21441444 is about 4630.4906867415. The cubic root of 21441444 is about 277.8122189947.

Adding to 21441444 its reverse (44414412), we get a palindrome (65855856).

The spelling of 21441444 in words is "twenty-one million, four hundred forty-one thousand, four hundred forty-four".