28790239 has 2 divisors, whose sum is σ = 28790240. Its totient is φ = 28790238.

The previous prime is 28790221. The next prime is 28790261. The reversal of 28790239 is 93209782.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28790239 - 2¹⁵ = 28757471 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28790219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14395119 + 14395120.

It is an arithmetic number, because the mean of its divisors is an integer number (14395120).

Almost surely, 2^28790239 is an apocalyptic number.

28790239 is a deficient number, since it is larger than the sum of its proper divisors (1).

28790239 is an equidigital number, since it uses as much as digits as its factorization.

28790239 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54432, while the sum is 40.

The square root of 28790239 is about 5365.6536414495. The cubic root of 28790239 is about 306.4891396631.

The spelling of 28790239 in words is "twenty-eight million, seven hundred ninety thousand, two hundred thirty-nine".