28579725 has 36 divisors (see below), whose sum is σ = 52588276. Its totient is φ = 14826240.

The previous prime is 28579723. The next prime is 28579729. The reversal of 28579725 is 52797582.

It is a happy number.

28579725 is a `hidden beast` number, since 2 + 8 + 579 + 72 + 5 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 9 + 28579716 = 3^2 + 5346^2 .

It is not a de Polignac number, because 28579725 - 2¹ = 28579723 is a prime.

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

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28579723) by changing a digit.

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 35 ways as a sum of consecutive naturals, for example, 6609 + ... + 10041.

Almost surely, 2^28579725 is an apocalyptic number.

28579725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28579725 is a deficient number, since it is larger than the sum of its proper divisors (24008551).

28579725 is a wasteful number, since it uses less digits than its factorization.

28579725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3486 (or 3478 counting only the distinct ones).

The product of its digits is 352800, while the sum is 45.

The square root of 28579725 is about 5346.0008417508. Note that the first 3 decimals coincide. The cubic root of 28579725 is about 305.7402961183.

The spelling of 28579725 in words is "twenty-eight million, five hundred seventy-nine thousand, seven hundred twenty-five".