278993 has 8 divisors (see below), whose sum is σ = 327936. Its totient is φ = 234000.

The previous prime is 278981. The next prime is 279001. The reversal of 278993 is 399872.

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

It is a de Polignac number, because none of the positive numbers 2^k-278993 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 12.

It is a zygodrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (278903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 833 + ... + 1118.

It is an arithmetic number, because the mean of its divisors is an integer number (40992).

2²⁷⁸⁹⁹³ is an apocalyptic number.

It is an amenable number.

278993 is a deficient number, since it is larger than the sum of its proper divisors (48943).

278993 is a wasteful number, since it uses less digits than its factorization.

278993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1975.

The product of its digits is 27216, while the sum is 38.

The square root of 278993 is about 528.1978795868. The cubic root of 278993 is about 65.3428042867.

It can be divided in two parts, 2789 and 93, that added together give a palindrome (2882).

The spelling of 278993 in words is "two hundred seventy-eight thousand, nine hundred ninety-three".