25440321 has 4 divisors (see below), whose sum is σ = 33920432. Its totient is φ = 16960212.

The previous prime is 25440319. The next prime is 25440341. The reversal of 25440321 is 12304452.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 25440321 - 2¹ = 25440319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25440341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4240051 + ... + 4240056.

It is an arithmetic number, because the mean of its divisors is an integer number (8480108).

Almost surely, 2^25440321 is an apocalyptic number.

It is an amenable number.

25440321 is a deficient number, since it is larger than the sum of its proper divisors (8480111).

25440321 is an equidigital number, since it uses as much as digits as its factorization.

25440321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8480110.

The product of its (nonzero) digits is 960, while the sum is 21.

The square root of 25440321 is about 5043.8399062619. The cubic root of 25440321 is about 294.1084680061.

Adding to 25440321 its reverse (12304452), we get a palindrome (37744773).

The spelling of 25440321 in words is "twenty-five million, four hundred forty thousand, three hundred twenty-one".