279 has 6 divisors (see below), whose sum is σ = 416. Its totient is φ = 180.

The previous prime is 277. The next prime is 281. The reversal of 279 is 972.

Subtracting from 279 its product of digits (126), we obtain a triangular number (153 = T_{17}).

It can be divided in two parts, 27 and 9, that multiplied together give a 5-th power (243 = 3^{5}).

279 is an esthetic number in base 11, because in such base its adjacent digits differ by 1.

It is an interprime number because it is at equal distance from previous prime (277) and next prime (281).

It is not a de Polignac number, because 279 - 2^{1} = 277 is a prime.

It is a Duffinian number.

It is a plaindrome in base 10, base 11, base 14, base 15 and base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7 + ... + 24.

279 is a deficient number, since it is larger than the sum of its proper divisors (137).

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

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

The sum of its prime factors is 37 (or 34 counting only the distinct ones).

The product of its digits is 126, while the sum is 18.

The square root of 279 is about 16.7032930885. The cubic root of 279 is about 6.5343350771.

The spelling of 279 in words is "two hundred seventy-nine", and thus it is an aban number.

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