21305041 has 8 divisors (see below), whose sum is σ = 21826368. Its totient is φ = 20790000.

The previous prime is 21305027. The next prime is 21305047. The reversal of 21305041 is 14050312.

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

It is a cyclic number.

It is not a de Polignac number, because 21305041 - 2¹¹ = 21302993 is a prime.

It is a super-3 number, since 3×21305041³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21305047) 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 7 ways as a sum of consecutive naturals, for example, 5686 + ... + 8656.

It is an arithmetic number, because the mean of its divisors is an integer number (2728296).

Almost surely, 2^21305041 is an apocalyptic number.

It is an amenable number.

21305041 is a deficient number, since it is larger than the sum of its proper divisors (521327).

21305041 is a wasteful number, since it uses less digits than its factorization.

21305041 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3143.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 21305041 is about 4615.7384024661. The cubic root of 21305041 is about 277.2218504487.

Adding to 21305041 its reverse (14050312), we get a palindrome (35355353).

The spelling of 21305041 in words is "twenty-one million, three hundred five thousand, forty-one".