21324430 has 16 divisors (see below), whose sum is σ = 38438784. Its totient is φ = 8517600.

The previous prime is 21324421. The next prime is 21324451. The reversal of 21324430 is 3442312.

It is a junction number, because it is equal to n+sod(n) for n = 21324398 and 21324407.

It is a congruent number.

It is an unprimeable number.

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, 9955 + ... + 11905.

It is an arithmetic number, because the mean of its divisors is an integer number (2402424).

Almost surely, 2^21324430 is an apocalyptic number.

21324430 is a deficient number, since it is larger than the sum of its proper divisors (17114354).

21324430 is a wasteful number, since it uses less digits than its factorization.

21324430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3051.

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 21324430 is about 4617.8382388299. The cubic root of 21324430 is about 277.3059217057.

Adding to 21324430 its reverse (3442312), we get a palindrome (24766742).

The spelling of 21324430 in words is "twenty-one million, three hundred twenty-four thousand, four hundred thirty".