280039 has 4 divisors (see below), whose sum is σ = 283024. Its totient is φ = 277056.

The previous prime is 280037. The next prime is 280061. The reversal of 280039 is 930082.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 930082 = 2 ⋅465041.

It is a cyclic number.

It is not a de Polignac number, because 280039 - 2¹ = 280037 is a prime.

It is a Duffinian number.

280039 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (280031) 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, 1347 + ... + 1540.

It is an arithmetic number, because the mean of its divisors is an integer number (70756).

2²⁸⁰⁰³⁹ is an apocalyptic number.

280039 is a deficient number, since it is larger than the sum of its proper divisors (2985).

280039 is an equidigital number, since it uses as much as digits as its factorization.

280039 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2984.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 280039 is about 529.1871124659. The cubic root of 280039 is about 65.4243634815.

Adding to 280039 its reverse (930082), we get a palindrome (1210121).

The spelling of 280039 in words is "two hundred eighty thousand, thirty-nine".