28724975 has 6 divisors (see below), whose sum is σ = 35619000. Its totient is φ = 22979960.

The previous prime is 28724963. The next prime is 28724981. The reversal of 28724975 is 57942782.

It is not a de Polignac number, because 28724975 - 2⁴ = 28724959 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 574475 + ... + 574524.

It is an arithmetic number, because the mean of its divisors is an integer number (5936500).

Almost surely, 2^28724975 is an apocalyptic number.

28724975 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

28724975 is a deficient number, since it is larger than the sum of its proper divisors (6894025).

28724975 is a wasteful number, since it uses less digits than its factorization.

28724975 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1149009 (or 1149004 counting only the distinct ones).

The product of its digits is 282240, while the sum is 44.

The square root of 28724975 is about 5359.5685460679. The cubic root of 28724975 is about 306.2573731392.

The spelling of 28724975 in words is "twenty-eight million, seven hundred twenty-four thousand, nine hundred seventy-five".