21456325 has 36 divisors (see below), whose sum is σ = 30130884. Its totient is φ = 15136000.

The previous prime is 21456319. The next prime is 21456341. The reversal of 21456325 is 52365412.

It can be written as a sum of positive squares in 6 ways, for example, as 717409 + 20738916 = 847^2 + 4554^2 .

It is not a de Polignac number, because 21456325 - 2²¹ = 19359173 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21456293 and 21456302.

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 35 ways as a sum of consecutive naturals, for example, 123939 + ... + 124111.

It is an arithmetic number, because the mean of its divisors is an integer number (836969).

Almost surely, 2^21456325 is an apocalyptic number.

21456325 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21456325 is a deficient number, since it is larger than the sum of its proper divisors (8674559).

21456325 is a wasteful number, since it uses less digits than its factorization.

21456325 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246 (or 230 counting only the distinct ones).

The product of its digits is 7200, while the sum is 28.

The square root of 21456325 is about 4632.0972571828. The cubic root of 21456325 is about 277.8764741136.

The spelling of 21456325 in words is "twenty-one million, four hundred fifty-six thousand, three hundred twenty-five".