21441573 has 24 divisors (see below), whose sum is σ = 32968728. Its totient is φ = 13381632.

The previous prime is 21441569. The next prime is 21441577. The reversal of 21441573 is 37514412.

It is an interprime number because it is at equal distance from previous prime (21441569) and next prime (21441577).

It can be written as a sum of positive squares in 4 ways, for example, as 6441444 + 15000129 = 2538^2 + 3873^2 .

It is not a de Polignac number, because 21441573 - 2² = 21441569 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21441577) 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 23 ways as a sum of consecutive naturals, for example, 53811 + ... + 54207.

It is an arithmetic number, because the mean of its divisors is an integer number (1373697).

Almost surely, 2^21441573 is an apocalyptic number.

It is an amenable number.

21441573 is a deficient number, since it is larger than the sum of its proper divisors (11527155).

21441573 is a wasteful number, since it uses less digits than its factorization.

21441573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 773 (or 770 counting only the distinct ones).

The product of its digits is 3360, while the sum is 27.

The square root of 21441573 is about 4630.5046161299. The cubic root of 21441573 is about 277.8127761354.

Adding to 21441573 its reverse (37514412), we get a palindrome (58955985).

The spelling of 21441573 in words is "twenty-one million, four hundred forty-one thousand, five hundred seventy-three".