21324205 has 16 divisors (see below), whose sum is σ = 30965760. Its totient is φ = 13761792.

The previous prime is 21324203. The next prime is 21324221. The reversal of 21324205 is 50242312.

It is a cyclic number.

It is not a de Polignac number, because 21324205 - 2¹ = 21324203 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21324203) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17325 + ... + 18514.

It is an arithmetic number, because the mean of its divisors is an integer number (1935360).

Almost surely, 2^21324205 is an apocalyptic number.

It is an amenable number.

21324205 is a deficient number, since it is larger than the sum of its proper divisors (9641555).

21324205 is a wasteful number, since it uses less digits than its factorization.

21324205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35868.

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 21324205 is about 4617.8138767170. The cubic root of 21324205 is about 277.3049463916.

Adding to 21324205 its reverse (50242312), we get a palindrome (71566517).

The spelling of 21324205 in words is "twenty-one million, three hundred twenty-four thousand, two hundred five".