278947 has 2 divisors, whose sum is σ = 278948. Its totient is φ = 278946.

The previous prime is 278917. The next prime is 278981. The reversal of 278947 is 749872.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 278947 - 2⁷ = 278819 is a prime.

It is a super-2 number, since 2×278947² = 155622857618, which contains 22 as substring.

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

It is not a weakly prime, because it can be changed into another prime (278917) 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 as a sum of consecutive naturals, namely, 139473 + 139474.

It is an arithmetic number, because the mean of its divisors is an integer number (139474).

2²⁷⁸⁹⁴⁷ is an apocalyptic number.

278947 is a deficient number, since it is larger than the sum of its proper divisors (1).

278947 is an equidigital number, since it uses as much as digits as its factorization.

278947 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 28224, while the sum is 37.

The square root of 278947 is about 528.1543335049. The cubic root of 278947 is about 65.3392128773.

It can be divided in two parts, 278 and 947, that added together give a triangular number (1225 = T₄₉).

The spelling of 278947 in words is "two hundred seventy-eight thousand, nine hundred forty-seven".