28751015 has 4 divisors (see below), whose sum is σ = 34501224. Its totient is φ = 23000808.

The previous prime is 28751011. The next prime is 28751027. The reversal of 28751015 is 51015782.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 51015782 = 2 ⋅25507891.

It is a cyclic number.

It is not a de Polignac number, because 28751015 - 2² = 28751011 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28751011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2875097 + ... + 2875106.

It is an arithmetic number, because the mean of its divisors is an integer number (8625306).

Almost surely, 2^28751015 is an apocalyptic number.

28751015 is a deficient number, since it is larger than the sum of its proper divisors (5750209).

28751015 is an equidigital number, since it uses as much as digits as its factorization.

28751015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5750208.

The product of its (nonzero) digits is 2800, while the sum is 29.

The square root of 28751015 is about 5361.9972957845. The cubic root of 28751015 is about 306.3498888376.

Adding to 28751015 its sum of digits (29), we get a square (28751044 = 5362²).

Adding to 28751015 its reverse (51015782), we get a palindrome (79766797).

The spelling of 28751015 in words is "twenty-eight million, seven hundred fifty-one thousand, fifteen".