21241165 has 16 divisors (see below), whose sum is σ = 28019520. Its totient is φ = 15329920.

The previous prime is 21241163. The next prime is 21241217. The reversal of 21241165 is 56114212.

It is not a de Polignac number, because 21241165 - 2¹ = 21241163 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21241163) 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 15 ways as a sum of consecutive naturals, for example, 6126 + ... + 8944.

It is an arithmetic number, because the mean of its divisors is an integer number (1751220).

Almost surely, 2^21241165 is an apocalyptic number.

It is an amenable number.

21241165 is a deficient number, since it is larger than the sum of its proper divisors (6778355).

21241165 is a wasteful number, since it uses less digits than its factorization.

21241165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2972.

The product of its digits is 480, while the sum is 22.

The square root of 21241165 is about 4608.8138387225. The cubic root of 21241165 is about 276.9445209435.

Adding to 21241165 its reverse (56114212), we get a palindrome (77355377).

The spelling of 21241165 in words is "twenty-one million, two hundred forty-one thousand, one hundred sixty-five".