21325345 has 8 divisors (see below), whose sum is σ = 26073576. Its totient is φ = 16738176.

The previous prime is 21325331. The next prime is 21325349. The reversal of 21325345 is 54352312.

It can be written as a sum of positive squares in 4 ways, for example, as 4809249 + 16516096 = 2193^2 + 4064^2 .

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 21325345 - 2⁵ = 21325313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21325349) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39972 + ... + 40501.

It is an arithmetic number, because the mean of its divisors is an integer number (3259197).

Almost surely, 2^21325345 is an apocalyptic number.

It is an amenable number.

21325345 is a deficient number, since it is larger than the sum of its proper divisors (4748231).

21325345 is an equidigital number, since it uses as much as digits as its factorization.

21325345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80531.

The product of its digits is 3600, while the sum is 25.

The square root of 21325345 is about 4617.9373100985. The cubic root of 21325345 is about 277.3098879124.

Adding to 21325345 its reverse (54352312), we get a palindrome (75677657).

The spelling of 21325345 in words is "twenty-one million, three hundred twenty-five thousand, three hundred forty-five".