28715243 has 4 divisors (see below), whose sum is σ = 28802328. Its totient is φ = 28628160.

The previous prime is 28715233. The next prime is 28715257. The reversal of 28715243 is 34251782.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34251782 = 2 ⋅17125891.

It is a cyclic number.

It is not a de Polignac number, because 28715243 - 2¹⁰ = 28714219 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28715233) 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, 43046 + ... + 43707.

It is an arithmetic number, because the mean of its divisors is an integer number (7200582).

Almost surely, 2^28715243 is an apocalyptic number.

28715243 is a deficient number, since it is larger than the sum of its proper divisors (87085).

28715243 is an equidigital number, since it uses as much as digits as its factorization.

28715243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87084.

The product of its digits is 13440, while the sum is 32.

The square root of 28715243 is about 5358.6605602520. The cubic root of 28715243 is about 306.2227826430. Note that the first 3 decimals are identical.

The spelling of 28715243 in words is "twenty-eight million, seven hundred fifteen thousand, two hundred forty-three".