28748239 has 8 divisors (see below), whose sum is σ = 31095792. Its totient is φ = 26420160.

The previous prime is 28748231. The next prime is 28748243. The reversal of 28748239 is 93284782.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28748239 - 2³ = 28748231 is a prime.

It is a super-2 number, since 2×28748239² = 1652922491202242, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28748195 and 28748204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28748231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1717 + ... + 7774.

It is an arithmetic number, because the mean of its divisors is an integer number (3886974).

Almost surely, 2^28748239 is an apocalyptic number.

28748239 is a deficient number, since it is larger than the sum of its proper divisors (2347553).

28748239 is a wasteful number, since it uses less digits than its factorization.

28748239 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9737.

The product of its digits is 193536, while the sum is 43.

The square root of 28748239 is about 5361.7384307704. The cubic root of 28748239 is about 306.3400288418.

The spelling of 28748239 in words is "twenty-eight million, seven hundred forty-eight thousand, two hundred thirty-nine".