21325135 has 16 divisors (see below), whose sum is σ = 28306656. Its totient is φ = 15320448.

The previous prime is 21325099. The next prime is 21325147. The reversal of 21325135 is 53152312.

It is not a de Polignac number, because 21325135 - 2¹¹ = 21323087 is a prime.

It is a super-2 number, since 2×21325135² = 909522765536450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 2029 + ... + 6838.

It is an arithmetic number, because the mean of its divisors is an integer number (1769166).

Almost surely, 2^21325135 is an apocalyptic number.

21325135 is a deficient number, since it is larger than the sum of its proper divisors (6981521).

21325135 is a wasteful number, since it uses less digits than its factorization.

21325135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8922.

The product of its digits is 900, while the sum is 22.

The square root of 21325135 is about 4617.9145726183. The cubic root of 21325135 is about 277.3089776454.

Adding to 21325135 its reverse (53152312), we get a palindrome (74477447).

The spelling of 21325135 in words is "twenty-one million, three hundred twenty-five thousand, one hundred thirty-five".