21325225 has 12 divisors (see below), whose sum is σ = 27999324. Its totient is φ = 16056320.

The previous prime is 21325219. The next prime is 21325279. The reversal of 21325225 is 52252312.

It can be written as a sum of positive squares in 6 ways, for example, as 3143529 + 18181696 = 1773^2 + 4264^2 .

It is not a de Polignac number, because 21325225 - 2³ = 21325217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21325196 and 21325205.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24664 + ... + 25513.

It is an arithmetic number, because the mean of its divisors is an integer number (2333277).

Almost surely, 2^21325225 is an apocalyptic number.

21325225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21325225 is a deficient number, since it is larger than the sum of its proper divisors (6674099).

21325225 is a wasteful number, since it uses less digits than its factorization.

21325225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50204 (or 50199 counting only the distinct ones).

The product of its digits is 1200, while the sum is 22.

The square root of 21325225 is about 4617.9243172664. The cubic root of 21325225 is about 277.3093677606.

Adding to 21325225 its reverse (52252312), we get a palindrome (73577537).

The spelling of 21325225 in words is "twenty-one million, three hundred twenty-five thousand, two hundred twenty-five".