21460321 has 8 divisors (see below), whose sum is σ = 21911400. Its totient is φ = 21013632.

The previous prime is 21460237. The next prime is 21460331. The reversal of 21460321 is 12306412.

It can be written as a sum of positive squares in 4 ways, for example, as 69696 + 21390625 = 264^2 + 4625^2 .

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 21460321 - 2¹⁹ = 20936033 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21460331) 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, 9891 + ... + 11863.

It is an arithmetic number, because the mean of its divisors is an integer number (2738925).

Almost surely, 2^21460321 is an apocalyptic number.

It is an amenable number.

21460321 is a deficient number, since it is larger than the sum of its proper divisors (451079).

21460321 is a wasteful number, since it uses less digits than its factorization.

21460321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2195.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 21460321 is about 4632.5285751952. The cubic root of 21460321 is about 277.8937235022.

Adding to 21460321 its reverse (12306412), we get a palindrome (33766733).

The spelling of 21460321 in words is "twenty-one million, four hundred sixty thousand, three hundred twenty-one".