278125 has 12 divisors (see below), whose sum is σ = 351540. Its totient is φ = 220000.

The previous prime is 278123. The next prime is 278143. The reversal of 278125 is 521872.

It can be written as a sum of positive squares in 6 ways, for example, as 259081 + 19044 = 509^2 + 138^2 .

It is not a de Polignac number, because 278125 - 2¹ = 278123 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a d-powerful number, because it can be written as 2² + 7³ + 1 + 8 + 2¹⁸ + 5⁶ .

It is an alternating number because its digits alternate between even and odd.

278125 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 278125.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (278123) 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 11 ways as a sum of consecutive naturals, for example, 3081 + ... + 3169.

It is an arithmetic number, because the mean of its divisors is an integer number (29295).

2²⁷⁸¹²⁵ is an apocalyptic number.

278125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

278125 is a deficient number, since it is larger than the sum of its proper divisors (73415).

278125 is an frugal number, since it uses more digits than its factorization.

278125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114 (or 94 counting only the distinct ones).

The product of its digits is 1120, while the sum is 25.

The square root of 278125 is about 527.3755777432. The cubic root of 278125 is about 65.2749692804.

Adding to 278125 its reverse (521872), we get a palindrome (799997).

The spelling of 278125 in words is "two hundred seventy-eight thousand, one hundred twenty-five".