21445325 has 12 divisors (see below), whose sum is σ = 29010048. Its totient is φ = 15596400.

The previous prime is 21445247. The next prime is 21445327. The reversal of 21445325 is 52354412.

It is a happy number.

It is not a de Polignac number, because 21445325 - 2¹² = 21441229 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21445294 and 21445303.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21445327) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 38717 + ... + 39266.

It is an arithmetic number, because the mean of its divisors is an integer number (2417504).

Almost surely, 2^21445325 is an apocalyptic number.

21445325 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21445325 is a deficient number, since it is larger than the sum of its proper divisors (7564723).

21445325 is a wasteful number, since it uses less digits than its factorization.

21445325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78004 (or 77999 counting only the distinct ones).

The product of its digits is 4800, while the sum is 26.

The square root of 21445325 is about 4630.9097378377. The cubic root of 21445325 is about 277.8289797467.

Adding to 21445325 its reverse (52354412), we get a palindrome (73799737).

The spelling of 21445325 in words is "twenty-one million, four hundred forty-five thousand, three hundred twenty-five".