278881 has 2 divisors, whose sum is σ = 278882. Its totient is φ = 278880.

The previous prime is 278879. The next prime is 278891. The reversal of 278881 is 188872.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 245025 + 33856 = 495^2 + 184^2 .

It is a cyclic number.

It is not a de Polignac number, because 278881 - 2¹ = 278879 is a prime.

It is a super-2 number, since 2×278881² = 155549224322, which contains 22 as substring.

Together with 278879, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (278801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139440 + 139441.

It is an arithmetic number, because the mean of its divisors is an integer number (139441).

2²⁷⁸⁸⁸¹ is an apocalyptic number.

It is an amenable number.

278881 is a deficient number, since it is larger than the sum of its proper divisors (1).

278881 is an equidigital number, since it uses as much as digits as its factorization.

278881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7168, while the sum is 34.

The square root of 278881 is about 528.0918480719. The cubic root of 278881 is about 65.3340592959.

Subtracting from 278881 its reverse (188872), we obtain a palindrome (90009).

It can be divided in two parts, 27888 and 1, that added together give a square (27889 = 167²).

The spelling of 278881 in words is "two hundred seventy-eight thousand, eight hundred eighty-one".