25328721 has 8 divisors (see below), whose sum is σ = 36841824. Its totient is φ = 15350720.

The previous prime is 25328717. The next prime is 25328749. The reversal of 25328721 is 12782352.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 25328721 - 2² = 25328717 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (25328711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 383736 + ... + 383801.

It is an arithmetic number, because the mean of its divisors is an integer number (4605228).

Almost surely, 2^25328721 is an apocalyptic number.

It is an amenable number.

25328721 is a deficient number, since it is larger than the sum of its proper divisors (11513103).

25328721 is a wasteful number, since it uses less digits than its factorization.

25328721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 767551.

The product of its digits is 6720, while the sum is 30.

The square root of 25328721 is about 5032.7647471345. The cubic root of 25328721 is about 293.6777787745.

The spelling of 25328721 in words is "twenty-five million, three hundred twenty-eight thousand, seven hundred twenty-one".