278911 has 2 divisors, whose sum is σ = 278912. Its totient is φ = 278910.

The previous prime is 278909. The next prime is 278917. The reversal of 278911 is 119872.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 278911 - 2¹ = 278909 is a prime.

Together with 278909, it forms a pair of twin primes.

278911 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 278911.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (278917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139455 + 139456.

It is an arithmetic number, because the mean of its divisors is an integer number (139456).

2²⁷⁸⁹¹¹ is an apocalyptic number.

278911 is a deficient number, since it is larger than the sum of its proper divisors (1).

278911 is an equidigital number, since it uses as much as digits as its factorization.

278911 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1008, while the sum is 28.

The square root of 278911 is about 528.1202514579. The cubic root of 278911 is about 65.3364019337.

The spelling of 278911 in words is "two hundred seventy-eight thousand, nine hundred eleven".