278995 has 4 divisors (see below), whose sum is σ = 334800. Its totient is φ = 223192.

The previous prime is 278981. The next prime is 279001. The reversal of 278995 is 599872.

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 278995 - 2⁷ = 278867 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a plaindrome in base 12.

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, 27895 + ... + 27904.

It is an arithmetic number, because the mean of its divisors is an integer number (83700).

2²⁷⁸⁹⁹⁵ is an apocalyptic number.

278995 is a deficient number, since it is larger than the sum of its proper divisors (55805).

278995 is an equidigital number, since it uses as much as digits as its factorization.

278995 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55804.

The product of its digits is 45360, while the sum is 40.

The square root of 278995 is about 528.1997728133. The cubic root of 278995 is about 65.3429604259.

The spelling of 278995 in words is "two hundred seventy-eight thousand, nine hundred ninety-five".