21241263 has 8 divisors (see below), whose sum is σ = 28408576. Its totient is φ = 14117400.

The previous prime is 21241261. The next prime is 21241271. The reversal of 21241263 is 36214212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21241263 - 2¹ = 21241261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21241261) 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 7 ways as a sum of consecutive naturals, for example, 9703 + ... + 11688.

It is an arithmetic number, because the mean of its divisors is an integer number (3551072).

Almost surely, 2^21241263 is an apocalyptic number.

21241263 is a deficient number, since it is larger than the sum of its proper divisors (7167313).

21241263 is a wasteful number, since it uses less digits than its factorization.

21241263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21725.

The product of its digits is 576, while the sum is 21.

The square root of 21241263 is about 4608.8244705131. The cubic root of 21241263 is about 276.9449468542.

Adding to 21241263 its reverse (36214212), we get a palindrome (57455475).

The spelling of 21241263 in words is "twenty-one million, two hundred forty-one thousand, two hundred sixty-three".