278131 has 4 divisors (see below), whose sum is σ = 317872. Its totient is φ = 238392.

The previous prime is 278123. The next prime is 278143. The reversal of 278131 is 131872.

278131 is nontrivially palindromic in base 13.

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

It is not a de Polignac number, because 278131 - 2³ = 278123 is a prime.

It is a super-2 number, since 2×278131² = 154713706322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (278111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19860 + ... + 19873.

It is an arithmetic number, because the mean of its divisors is an integer number (79468).

2²⁷⁸¹³¹ is an apocalyptic number.

278131 is a deficient number, since it is larger than the sum of its proper divisors (39741).

278131 is an equidigital number, since it uses as much as digits as its factorization.

278131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39740.

The product of its digits is 336, while the sum is 22.

The square root of 278131 is about 527.3812662581. The cubic root of 278131 is about 65.2754386701.

The spelling of 278131 in words is "two hundred seventy-eight thousand, one hundred thirty-one".