21441164 has 12 divisors (see below), whose sum is σ = 37632000. Its totient is φ = 10689168.

The previous prime is 21441137. The next prime is 21441169. The reversal of 21441164 is 46114412.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21441169) 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, 6284 + ... + 9075.

It is an arithmetic number, because the mean of its divisors is an integer number (3136000).

Almost surely, 2^21441164 is an apocalyptic number.

It is an amenable number.

21441164 is a deficient number, since it is larger than the sum of its proper divisors (16190836).

21441164 is a wasteful number, since it uses less digits than its factorization.

21441164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15712 (or 15710 counting only the distinct ones).

The product of its digits is 768, while the sum is 23.

The square root of 21441164 is about 4630.4604522661. The cubic root of 21441164 is about 277.8110096893.

Adding to 21441164 its reverse (46114412), we get a palindrome (67555576).

The spelling of 21441164 in words is "twenty-one million, four hundred forty-one thousand, one hundred sixty-four".