278291 has 4 divisors (see below), whose sum is σ = 299712. Its totient is φ = 256872.

The previous prime is 278279. The next prime is 278321. The reversal of 278291 is 192872.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 278291 - 2⁶ = 278227 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 278291.

It is not an unprimeable number, because it can be changed into a prime (278261) 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, 10691 + ... + 10716.

It is an arithmetic number, because the mean of its divisors is an integer number (74928).

2²⁷⁸²⁹¹ is an apocalyptic number.

278291 is a deficient number, since it is larger than the sum of its proper divisors (21421).

278291 is a wasteful number, since it uses less digits than its factorization.

278291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21420.

The product of its digits is 2016, while the sum is 29.

The square root of 278291 is about 527.5329373603. The cubic root of 278291 is about 65.2879532383.

The spelling of 278291 in words is "two hundred seventy-eight thousand, two hundred ninety-one".