21324135 has 64 divisors (see below), whose sum is σ = 41472000. Its totient is φ = 9149952.

The previous prime is 21324119. The next prime is 21324139. The reversal of 21324135 is 53142312.

It is not a de Polignac number, because 21324135 - 2⁴ = 21324119 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

Its product of digits (720) is a multiple of the sum of its prime divisors (240).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21324139) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 143041 + ... + 143189.

It is an arithmetic number, because the mean of its divisors is an integer number (648000).

Almost surely, 2^21324135 is an apocalyptic number.

21324135 is a deficient number, since it is larger than the sum of its proper divisors (20147865).

21324135 is a wasteful number, since it uses less digits than its factorization.

21324135 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240.

The product of its digits is 720, while the sum is 21.

The square root of 21324135 is about 4617.8062973667. The cubic root of 21324135 is about 277.3046429591.

Adding to 21324135 its reverse (53142312), we get a palindrome (74466447).

The spelling of 21324135 in words is "twenty-one million, three hundred twenty-four thousand, one hundred thirty-five".