28748515 has 4 divisors (see below), whose sum is σ = 34498224. Its totient is φ = 22998808.

The previous prime is 28748509. The next prime is 28748521. The reversal of 28748515 is 51584782.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (28748509) and next prime (28748521).

It is a cyclic number.

It is not a de Polignac number, because 28748515 - 2¹⁵ = 28715747 is a prime.

It is a super-2 number, since 2×28748515² = 1652954229410450, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2874847 + ... + 2874856.

It is an arithmetic number, because the mean of its divisors is an integer number (8624556).

Almost surely, 2^28748515 is an apocalyptic number.

28748515 is a deficient number, since it is larger than the sum of its proper divisors (5749709).

28748515 is an equidigital number, since it uses as much as digits as its factorization.

28748515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5749708.

The product of its digits is 89600, while the sum is 40.

The square root of 28748515 is about 5361.7641686296. The cubic root of 28748515 is about 306.3410091868.

The spelling of 28748515 in words is "twenty-eight million, seven hundred forty-eight thousand, five hundred fifteen".