21053241 has 24 divisors (see below), whose sum is σ = 33496320. Its totient is φ = 12636000.

The previous prime is 21053203. The next prime is 21053267. The reversal of 21053241 is 14235012.

21053241 = 870² + 871² + ... + 896².

It is not a de Polignac number, because 21053241 - 2⁹ = 21052729 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21053281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9816 + ... + 11766.

It is an arithmetic number, because the mean of its divisors is an integer number (1395680).

Almost surely, 2^21053241 is an apocalyptic number.

It is an amenable number.

21053241 is a deficient number, since it is larger than the sum of its proper divisors (12443079).

21053241 is a wasteful number, since it uses less digits than its factorization.

21053241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2077 (or 2074 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 21053241 is about 4588.3810870502. The cubic root of 21053241 is about 276.1253762451.

Adding to 21053241 its reverse (14235012), we get a palindrome (35288253).

The spelling of 21053241 in words is "twenty-one million, fifty-three thousand, two hundred forty-one".