278155 has 4 divisors (see below), whose sum is σ = 333792. Its totient is φ = 222520.

The previous prime is 278149. The next prime is 278177. The reversal of 278155 is 551872.

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

It is not a de Polignac number, because 278155 - 2³ = 278147 is a prime.

It is a Duffinian number.

278155 is a lucky number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27811 + ... + 27820.

It is an arithmetic number, because the mean of its divisors is an integer number (83448).

2²⁷⁸¹⁵⁵ is an apocalyptic number.

278155 is a deficient number, since it is larger than the sum of its proper divisors (55637).

278155 is an equidigital number, since it uses as much as digits as its factorization.

278155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55636.

The product of its digits is 2800, while the sum is 28.

The square root of 278155 is about 527.4040197041. The cubic root of 278155 is about 65.2773161612.

The spelling of 278155 in words is "two hundred seventy-eight thousand, one hundred fifty-five".