278257 has 8 divisors (see below), whose sum is σ = 321536. Its totient is φ = 235872.

The previous prime is 278237. The next prime is 278261. The reversal of 278257 is 752872.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 278257 - 2¹¹ = 276209 is a prime.

It is a d-powerful number, because it can be written as 2⁵ + 7² + 2¹⁸ + 8² + 5⁶ + 7³ .

It is the 528-th Hogben number.

It is a Duffinian number.

278257 is a lucky number.

It is a nialpdrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (278207) by changing a digit.

It is a nontrivial repunit in base 527.

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 7 ways as a sum of consecutive naturals, for example, 733 + ... + 1045.

It is an arithmetic number, because the mean of its divisors is an integer number (40192).

2²⁷⁸²⁵⁷ is an apocalyptic number.

It is an amenable number.

278257 is a deficient number, since it is larger than the sum of its proper divisors (43279).

278257 is a wasteful number, since it uses less digits than its factorization.

278257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 447.

The product of its digits is 7840, while the sum is 31.

The square root of 278257 is about 527.5007109000. The cubic root of 278257 is about 65.2852942940.

It can be divided in two parts, 278 and 257, that added together give a palindrome (535).

The spelling of 278257 in words is "two hundred seventy-eight thousand, two hundred fifty-seven".