28249725 has 36 divisors (see below), whose sum is σ = 54338784. Its totient is φ = 12912480.

The previous prime is 28249723. The next prime is 28249729. The reversal of 28249725 is 52794282.

It is not a de Polignac number, because 28249725 - 2¹ = 28249723 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28249721) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 169 + ... + 7518.

Almost surely, 2^28249725 is an apocalyptic number.

28249725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28249725 is a deficient number, since it is larger than the sum of its proper divisors (26089059).

28249725 is a wasteful number, since it uses less digits than its factorization.

28249725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7714 (or 7702 counting only the distinct ones).

The product of its digits is 80640, while the sum is 39.

The square root of 28249725 is about 5315.0470364805. The cubic root of 28249725 is about 304.5589791951.

The spelling of 28249725 in words is "twenty-eight million, two hundred forty-nine thousand, seven hundred twenty-five".