28251729 has 24 divisors (see below), whose sum is σ = 44864352. Its totient is φ = 16989120.

The previous prime is 28251709. The next prime is 28251733. The reversal of 28251729 is 92715282.

It is not a de Polignac number, because 28251729 - 2⁵ = 28251697 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28251693 and 28251702.

It is not an unprimeable number, because it can be changed into a prime (28251709) 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 23 ways as a sum of consecutive naturals, for example, 12522 + ... + 14604.

It is an arithmetic number, because the mean of its divisors is an integer number (1869348).

Almost surely, 2^28251729 is an apocalyptic number.

It is an amenable number.

28251729 is a deficient number, since it is larger than the sum of its proper divisors (16612623).

28251729 is a wasteful number, since it uses less digits than its factorization.

28251729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2237 (or 2234 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 28251729 is about 5315.2355545168. The cubic root of 28251729 is about 304.5661807019.

It can be divided in two parts, 2825 and 1729, that added together give a palindrome (4554).

The spelling of 28251729 in words is "twenty-eight million, two hundred fifty-one thousand, seven hundred twenty-nine".