28259139 has 4 divisors (see below), whose sum is σ = 37678856. Its totient is φ = 18839424.

The previous prime is 28259113. The next prime is 28259159. The reversal of 28259139 is 93195282.

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

It is not a de Polignac number, because 28259139 - 2⁸ = 28258883 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28259097 and 28259106.

It is not an unprimeable number, because it can be changed into a prime (28259159) 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, 4709854 + ... + 4709859.

It is an arithmetic number, because the mean of its divisors is an integer number (9419714).

Almost surely, 2^28259139 is an apocalyptic number.

28259139 is a deficient number, since it is larger than the sum of its proper divisors (9419717).

28259139 is an equidigital number, since it uses as much as digits as its factorization.

28259139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9419716.

The product of its digits is 38880, while the sum is 39.

The square root of 28259139 is about 5315.9325616490. The cubic root of 28259139 is about 304.5928060708.

The spelling of 28259139 in words is "twenty-eight million, two hundred fifty-nine thousand, one hundred thirty-nine".