28678725 has 24 divisors (see below), whose sum is σ = 52685120. Its totient is φ = 15294960.

The previous prime is 28678717. The next prime is 28678739. The reversal of 28678725 is 52787682.

It is not a de Polignac number, because 28678725 - 2³ = 28678717 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

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 23 ways as a sum of consecutive naturals, for example, 20569 + ... + 21918.

Almost surely, 2^28678725 is an apocalyptic number.

28678725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28678725 is a deficient number, since it is larger than the sum of its proper divisors (24006395).

28678725 is a wasteful number, since it uses less digits than its factorization.

28678725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42506 (or 42495 counting only the distinct ones).

The product of its digits is 376320, while the sum is 45.

The square root of 28678725 is about 5355.2520949065. The cubic root of 28678725 is about 306.0929168041.

It can be divided in two parts, 28678 and 725, that added together give a triangular number (29403 = T₂₄₂).

The spelling of 28678725 in words is "twenty-eight million, six hundred seventy-eight thousand, seven hundred twenty-five".